Unrelated question: why can't aviation be more simple? I know it sounds dumb at first but let's say tesla decides to re invent air travel and open airports with simple universal lights and approach systems beacons etc. And also rethink the plane maintaining safety and redundancy but more user friendly I guess. Seems like there's more three letter words and designations for stuff than you can shake a stick at and I sometimes wonder how much of it is repeated by having different words for things and standards and stuff and how much is really important or needed anyway we have so much technology nowadays that I don't understand why I can get in a plane and just fly would love a pilots opinion
@@francopetre6171 Perhaps, if you really want to find out, and not just expecting someone else to do the thinking for you, go to your local flight school, get a trial lesson, you will answer your own question as you climb past the runway edge on departure . . .
Two anecdotes from my days as ground crew.......... 1) Mobile belt was left idling and uncrewed whilst waiting for a plane to arrive at the gate. The gearlever didn't engage into PARK properly and managed to slip into drive (they vibrate a lot). It took several seconds before anyone noticed that it had gone missing and then there was a scramble for anything that moved, to catch it (already crossing a live taxiway) before it hit a widebody parked on another terminal. There was a daredevil leap onto it and the widebody was saved. 2) Aircraft just stopped at the gate, chocks going on. Mobile belt already had the belt raised and was moving into position. The driver applied the brakes...nothing happened (a brake disc had fractured). The driver 'bravely' jumped overboard (no point having a steering wheel jammed into your gut) and the belt hit the aircraft. It was an ATP - it was tired and wanted to sleep, so it let its tail droop sadly. It stayed on the gate for a couple of days before being removed and fed to some chainsaws - I beleive that cost our insurers about £6.5 million (that was the figure bandied around the crew room - 6.5 for a leggy ATP? Maybe it grew whilst doing the rounds). I had an alibi for both :-P
@@MentourPilot at what stage of pre-flight checks are you supposed to hug the aircraft? who is responsible for it? how long can a 737ng go without hugs? (i know it must not be supposed to happen, but maybe it's been crewed by unfriendly people for a few legs).
I used to be a ramper for northwest airlines many years ago. One of the first things we do after the plane is parked and the beacons are turned off, the rampers would chalk all outer wheels and the nose wheel. Then give the signal to the crew wheels are chocked and free to release the parking brake.
The best one I heard was from years ago at one of the New York airports, the cleaners came into the terminal in early morning, to find a large jet sticking through the window, after it had rolled free, it was like a scene from Airplane. The morning rush was starting in less than an hour, and the sight might have made some nervous flyers terrified. However, when the crowds started to arrive, they saw a tidy 'exhibit', surrounded by every pot plant in the airport. The aircraft was quietly removed that night....
Bit more info, the ground crew removed the chocks about 45 mins previous to the aircraft starting to roll. I believe the plane was being prepped for return to the leasing company. I don't work as a pilot or ground crew but I would have thought that the chocks should stay in place until either the plane is ready to move under its own power or is hooked up to a ground tug.
Is it not SOP that they would not be removed until the plane was just about to start rolling with a crew in the cockpit and the engines about to be started?
william Mitchell not so the D8-Q400 has a DC Hydraulic Pump that runs off the aircraft battery and ensures hydraulic pressure for the parking brake as well as providing other emergency functions.
@@andybashford8648 The DC Hydraulic Pump powers only the elevator, in a separate hydraulic system, as a backup in case one or both main hydraulic systems fail. It does not pressurise the parking brake.
Hey Mentour, you are absolutely right about the hydraulic hand pump. It can be used to increase pressure to the #2 hydraulic accumulator that supplies pressure to the parking brake. Sadly I don't believe this could be used under the circumstances, here are my thoughts: Here's what would have to be done: Someone would have to enter the cockpit, ensure the parking brake is set, open the main gear doors using the manual alternate release handle, as the pump is accessed with the main gear doors open, remove the hand pump handle from the cockpit (it is the same used for alternate gear extension in case of hydraulic failure) and run out to engine 2 to operate the hand pump. This would increase the accumulator pressure and apply the parking brake, stopping the aircraft. The problem is that the pump is too high to reach without a step ladder, or one could climb onto the wheel to reach it, but both these methods are not feasible with a plane rolling and in the time available. I don't see how even someone who knew exactly what needs to be done would be able to pull this off under the circumstances. Here is some pure speculation: as you said, accumulator pressure decreases over time, so perhaps there was just enough pressure left to hold the aircraft still. If someone inadvertently, or without thinking it would matter, released the parking brake in the cockpit, that pressure would be lost, and even applying the parking brake again would have to effect, as the pressure in the accumulator would be depleted.
I worked on an RAF base and they had a Harrier jump jet being washed, it rolled away and poked its nose through the door of the next hangar.After that they had chocks and a tug connected with a guy sitting in it.
I was the aircraft washer on this Harrier jump jet. It happened on July the 23rd 2003. It had come into me for a backend wash. Which was from the tail fin to the rear nozzle. Job took me about half a hour once done I informed my supervisor that the jet was finished and ready for collection by the squadron who’s aircraft it was. I returned to my porta Kabin to await collection of the jet. Whilst having my break I heard a noise went to look and out the corner of my eye I saw the jet moving on it’s own it rolled of my pan across the road hit a cherry picker/access platform before sticking it’s nose to the outside of the hangar. It turned out following the investigation into the incident that the squadron had not put a enough air to the brakes and as a result with the aircraft started to slide on the cleaning fluid Gel and that started the aircraft on its journey. I have a couple of pictures of it on my instagram page halliday8995
Similar here, aircraft being towed out of the bay it was in. However there was miscommunication, and they did not disconnect the nose wheel steering link pin, so as the tug and the tow bar turned, the nose wheel did not. Frangible link did as intended, and broke, disconnecting the aircraft from the tow bar, and, as it was now on the slight incline out of the bay, it rolled down till it stopped in the reinforced earth berm 10m away. Guy in cockpit was pumping the brakes, but as there was no power, as battery was disconnected and removed, and he had no time to use the hand hydraulic pump either, so it rolled till stopped. Unfortunately the furtherest point forward was the pitot static tube, which pushed back, shearing it's mounting points, and moving back around a meter into the nose. Then the radome tip hit the wall, and penetrated the 3mm steel sheet. Radome actually survived intact, no damage to it or the rest of the radar cover at all. Unfortunately not so for the pitot probe, and the space behind it, which was the main electrical control box for the aircraft, and the aluminium alloy probe pole sheared through it right in the middle, cutting the main mount that held all the aircraft relays almost in half, relays, wiring and breakers and all. Damage was repaired in under 2 weeks, because there was another airframe undergoing a full rebuild, and that nose section was completed already in the rebuild, so it was shipped out, and put on in place of the original, which then went to have it's 7 figure rebuild, delaying the other aircraft only by around a month overall, but more than doubling the overhaul cost. That aircraft was odd till it's next major service, having 2 distinct different paint schemes on it front and rear. There was quite a bit of fall out from that, but luckily I was a spectator, though did get to see all the carnage up close, as the radome came in for inspection, along with the nose of the aircraft landing up outside our service unit doors for a month.
Like in the movie “Airplane,” couldn’t they have just manually inflated the autopilot? “I just want to tell you both, good luck, we’re all counting on ya.”
Wheel chocks are CHEAP... take a 6X6, cut at diagonal to make triangular shape. Cut to desired length(s). Drill and add a rope for convenience. Paint the wood a bright color. (So the pilot can see that the chocks are in place as they board the aircraft instead of trying to power over them.) Really low tech and highly effective.
@@hawk_7000 More likely they were in a hanger far away, and habit of "we never use them, it will only be here an hour at most" meant they were in the hanger still. I remember my erstwhile trainer coming in white as a sheet, because he was out flying, and they had a fire warning, so put down on the nearest thing to level, then the pilot kept the helicopter planted down hard, while all were out looking for suitable boulders to chock the wheels. Only when the wheels were suitably boulder impeded did he finally power down the engines, and pull the fire extinguisher handles to put out the fire burning up on the top, then they went up after rotor stop and put the remainder out. Radio call came in for somebody to bring out the required hydraulic hoses, the tools to change them, torches, a lot of hydraulic fluid to fill the reservoir again, some cleaning material and something to drink. He left 07H30, and came in white as a sheet at 15H20, from what was to have been a 2 hour training flight. Next day fire bottles replaced, and the extinguisher sent in for service, and all the rest of the fleet had those same hoses checked, and a month later all new PTFE stainless steel braid reinforced hoses installed in place of the original rubber. Took a day to wash that oil off the chopper, it was literally in every panel and compartment, along with the soot.
Peter, I've been called "micklin" after the character on "blscksheep squadron" for years. Your technical videos further my lifelong interest in the mechanics in aircraft. Thank you so much and keep up the good work!!!!
1:40 They were actually putting themselves in a potentially dangerous position by standing in front of the wheels whilst it rolled. One slip and they would have been crushed.
Don’t forget to lace your chocks. Working at Hill Air Force Base on F-4s in the late 70s. Our pro super was always telling us to lace the chocks, thought he was just busting our chops and wanted the flight line to look tidy. Well it rain one day so hard that I saw some of the chocks flot away down the ramp
The video is up there, really deserves a David Attenborough voice over. 'Here we see Aircraft in their natural environment, they assess each other and move cautiously for a closer inspection etc'.
I used to work at an airport and every morning we would tow a plane that had been sitting in remote parking overnight and by that time there was usually barely any hydraulic pressure left. So before towing we would always start the APU so we could pressurize the brakes (among other reasons).
I am retired from the railway where I was a train driver. We had the same problem where the loco brakes relied on compressed air and the handbrakes were sometimes dodgy. If a loco was parked on a gradient for any length of time it was possible for the compressed air to leak away, the handbrake fail and I can tell you that when 149 tons of loco starts to move on its own it will take a lot of stopping.
Earlier today, I had watched a fascinating video where they ground tested each engine while attached to the jet. The chocks used were absolutely huge, and when each engine was throttled up one at a time which resulted in the whole jet vibrating. Just sharing that that was amazing to watch. I didn't know that they tested each engine full throttle on the ground. I enjoyed your video today very much too. I agree that the chocks are very important to use. Take care!
I used to work at Phoenix Sky Harbor Airport, they had a place called Dynair that refurbishes Jets and does maintenance. I remember listening to the run up on a DC-10, alot of smoke at first then you could feel the Earth move when they throttled that up.
@@jasoncentore1830 Hey PHX! Yep, back in the day. Was that before, or after SabreTech owned the hangar? SabreTech ceased to exist after their Florida operation contributed heavily to the ValuJet 592 crash.
Just amazing. In all my flights, I have never seen a commercial plane temporarily park at a gate where the very, very first thing done was not chocking the wheels. The ramp crews ALWAYS put those in place first thing. I cannot recall a single flight where I did not see this done, even for very short turnarounds. I am just astounded that this was not done.
This video brings back memories. My car was the victim of a "no humans involved" crash in a parking lot when the other vehicle didn't have the parking brake set. I've chosen the high ground for parking ever since!
This makes me laugh because it recalls an incident in my own business. I worked in France on canal hire boats. We had an enormous amount of damage at the rear of our boats and had to suppress a feature because of it. Our boss kept telling us about how great the boats in another region were and how they never had any damage. One day a lorry delivered a boat from the said region and it was craned into the water. As the driver was in the office signing the paperwork, I heard a noise and the brakes on the lorry gave way. It ran backwards and smashed the part of the boat we had to repair on our own. 10 minutes and the damage was done. ;-D))
That's why the railroad cars brakes when the pressure is lost. Same with air brakes on trucks, so when the pressure is lost and it has to be towed then the air bells have to be "caged".
@@ehsnils Nonsense. Big trucks have spring brakes that holds it in place. When air pressure is lost, the brakes stay on. Don't argue please, I'm a mechanic and drive buses and 18 wheelers.
The big Sprinter van I drove for work slipped out of gear after I parked it at 4am and rolled into me as I was walking in front of it towards my coworkers house on the opposite side of the street to drop the keys in her mailbox. It pinned me against the vehicle parked in front of it. The street had an incline and that's why it rolled forward and into me. My cellphone was in my back pocket and I couldn't reach it. Nobody was on the street at that hour. I was really crushed and pinned tightly. I felt like I was going to go into shock. All I can remember after that was getting determined to free myself. I don't know how I pushed that big van back uphill but I did, and I wiggled out and temporarily lost consciousness when my blood flow was adjusting. I have very low blood pressure. I weighed about 110 lbs at the time. I was black and blue and deep purple for weeks on the lower half of my body.
I used to do line maintenance on those aircraft. Pumping the brake accumulator with the black and yellow pole take about 10 minutes and won't be achievable in that situation.
What's interesting is that I read an article earlier in the week that said there were two pilots on board who were taxiing and crashed into the other plane. Which kind of explains modern media today. "Hear about an incident, make up our own details, and report it as fact."
The hand pump is in the right MLG bay. It pressurises the parking brake accumulator and nothing else. If my memory serves me, you have to release the hydraulically operated gear doors (the Q400 has two sets, FWD "mechanical" that remain open after extension and AFT "hydraulicaly operated" that close) to get at it. If I remember correctly, if the brake lever is set cranking that pump should pressurise the brakes. The trick is to get at the handle, it's mounted pretty high in the bay. You have to remove it from the bulkhead and insert it in to the socket in the pump. I'd say the chances of someone opening the doors, removing the handle and cranking up enough pressure for the breaks to bite as the aircraft is moving is... ZERO.
FYI, the Dash 8 is formally known as the De Havilland Canada Dash 8 Q400. Bombardier sold the whole aircraft program to Longview Aviation Capital Corporation in 2018, and the deal closed in mid 2019. Longview revived the De Havilland name to brand the aircraft.
Thank you for saying "there is no system that is perfect" in reference to fluid systems. I had a guy hounding me for a few days when I mentioned that same concept in reference to fuel systems and acceptable amounts of leakage. I tried explaining, but he cited all sorts of qualifications he had earned, called me some pretty radio-unfriendly things and told me if he ever found me he would report me. haha. Your insight is always appreciated. Cya round 👊😎
There's nothing more ironic than someone using their qualifications to try to hold a position that is so obviously wrong. It's like they're trying to prove that those credentials aren't worth the paper they're printed on.
I've seen more than a few light planes where there is a set of chocks in the back so when you park somewhere you can secure the aircraft if there is not a tiedown
Swiss Surfer - In strong and gusty winds aircraft are turned nose into wind and, where possible a tow bar attached to the nose landing gear and a tug attached to the tow bar. This helps to prevent the aircraft from ‘weather-vaning’; ie: literally swinging round.
On a Semi tractor trailer (lorry), the brakes are spring loaded and always engaged, and requires about 110-120 p.s.i. of pneumatic pressure from the tractor in order to release them so it will roll.
And when you release the brakes onto the chocks, it can wedge the chocks in there good! I had on one occasion, the need to hammer the aft nose chock out with the forward chock and the whole CRJ200 dropped when it finally broke loose! Marshaller said the pilots were a little shaken!
My stepdaughter had to do that multiple times on an A-320, she said you should see the pilots face when she came around the corner with a sledgehammer draped on her shoulder, for some reason Pilots hate when you have to beat up on there plane with a hammer
Cool! Question: does the number of wheels that have to be chocked increase with even bigger aircraft (with more wheels)? Keep up the absolutely fantastic work!
I have a question for a future video please... during COVID obviously fewer planes are flying. Are planes ‘rotated’ across the routes that are running to ensure they all get used a little, or are some of them basically mothballed until needed. If they are mothballed, what additional checks, if any, are undertaken before the plane is put back into service? What could go wrong because they have been ‘sitting’? I’m not asking as a nervous flyer by the way, just interested. My car feels ‘different’ after just a few weeks of not being used. Thanks. You do fascinating videos even to someone like me who isn’t in aviation at all.
Damn.. you're not allowed to park even semi trailers without wedges in Finland. And those trailers have *brakes that lock by removing pressure* meaning only way to release the brake is to re-pressurize the system. Why would you ever park a plane without chocks?
I remember a couple of months ago where something similar happened between a Qatar Airways 787 and A350. It's really sad how people went out of their way to blame Boeing for that.
The major reason for static hydraulic systems to lose pressure is due to thermal expansion. When ambient temperature increased this causes an increase of pressure in the hydraulic system then the overpressure relief valves open and let this excess pressure out. When ambient temperature decrease there is a corresponding drop of pressure in the system.
That's interesting. In a tractor trailer, you need pressure to RELEASE the brakes. With no pressure, the spring will just hold the brakes locked until the driver applies air pressure. The only time we chock wheels are during repairs, or when the company has an engine cutoff in the truck, so the driver will override the cutoff by releasing his brakes and chocking the wheels.
I worked for 2 airlines - American and United Express ( Westair - contract carrier) as a Ramp agent and even as the push back tug was hooked up to the aircraft the nose gear and main gear stayed chocked
Those ramp rats should have verified the aircraft was chocked and grounded before touching it. It’s the first step in every maintenance checklist I’ve seen.
Not a slope - ABZ is usually really windy as it’s by the North Sea. The panicked workers trying to push it made me chuckle, but they also put themselves in danger.
This is indeed a strange phenomenon. I used to drive 18 wheelers, and you can stop on a level surface, not apply the handbrake, and the vehicle can start rolling after standing still for hours. Very strange, and a reminder that it's best to double check the park brake is properly set.
I suppose the problem just becomes more tricky for heavy vehicles, with all that inertia... Both the "sneaky" start of the roll and then taking a lot to stop once they get going.
I appreciate the ground workers wanting to stop it, but that isn't wise. I once watched a truck driver run over himself with his own truck. He didn't set the parking brake, and it started to roll. He grabbed a set of drive tires to try to stop it. He got pulled under, and crushed his legs. If he just let it go, it would have crashed into a nearby wall and taken damage, but he would be walking. I ran over from my truck, got it in gear and moved it off him, called an ambulance, and took care of him the best I could until the paramedics got there. I'm satisfied that I did what could be done, and don't question my own actions after the fact. But.... When it was over, I puked so hard my belly was sore the rest of the day. Years later, I still vividly remember his screaming.
Great video. I love how you explain these things in such detail, it is only here on your channel that it is possible to really learn these technical details. A thing such as the parking brake on the 737, I always assumed it would be a separate braking system. I hope to be a 737 pilot after university and I’ve learned a tonne from you. Thank you Petter :) Chris
Fun fact, the chocks have also caused a 737 emergency landing too... In flight Piedmont Airlines Flight 1489 The poor captain was unable to lower the landing gear as the chocks were stowed improperly in the well and slid in to block the extension of the gear. After inducing some Gs he was able to shake lose one of the gears, but had to use the engine cowling for the other.
I’ve asked this question before and if there was an answer I missed it, apologies if so. Why not use the road transport “spring release” parking brake, albeit a beefed up version. Ergo with no system pressure the wheels are locked by the spring pressure.
Weight, plus the reason they're fitted to trucks (in case of catastrophic air loss) is more likely than that you get a rogue activation of a spring brake. While extremely rare rogue activation can happen & the resulting skid is dangerous & spectacular if it happens when moving, the consequences of such a rogue activation on an airliner during takeoff or landing don't bear thinking of, they come on on one setting (full) & being a dumb mechanical system can't incorporate anti-skid or ABS. Aircraft already have multiple hydraulic systems to mitigate the failure of one, & thrust reversers as an alternate to brakes on landing if brakes should fail. Secondly, chocks provide visual confirmation to ground crew that the aircraft is secure, in haulage & transport generally drivers forgetting to set the parking brake isn't as uncommon as everyone would like & the only way you'll know the vehicle isn't secure is when it moves long before the air bled down enough for the spring brake to activate, all too frequently causing injury in addition to damage. Finally spring brakes can themselves fail (broken spring, corrosion, seizure) without any visual indication it has happened, chocks don't suffer from those problems. The potential failures are not using them (obvious to everyone), using chocks that are the wrong size (typically too small, also apparent to anyone passing) and chocks slipping on ice/spills/poor surfaces etc. In these days of not being able to rely on common sense & lawsuits about everything, that means training for people setting them. Technically I've little doubt such a spring backed parking brake system could be engineered along with a system to prevent activation at dangerous moments, it would be expensive to do, probably more so to certify, would add to operating costs both through another system to inspect & maintain plus the cost of carrying the weight, I doubt it would be mandated unless there's a serious accident chocks wouldn't have prevented first. The failures here were to set chocks, & train work crews that they should check for them being set. Fun fact: If a haulage company expects to stand trucks or trailers for an extended period of say weeks or months, especially in winter, they'll often use chocks & store the vehicle/trailer with brakes off and spring brakes disabled to prevent them locking or freezing on.
hi Mentour, have you seen the film 7500 just released by Amazon? it is entirely shot in an (Airbus?) Cockpit, I would be curious to hear your review! :) I guess the title gives you quite some hint as to what it is about!
I may be wrong, but my instinct would have been to get in to the seat and use the nose wheel staring turn left or right to counter the incline. Would that have worked? Or would the lack of hydraulic pressure been an issue?
I'm a truck driver and we use (pneumatic) pressure to RELEASE the parking break, not set it, just to avoid situations like this from happening. Do you know why airplanes are not designed in a similar way?
I dont know about the q400 but the 737 has a brake accumulator that is charger with nitrogen which is around 1500-1800 psi that holds the brake pressure when the hydraulic pressure is not available. However a bad accumulator bleeds the nitrogen and the brake will be less effective and if the chokes are not there it will roll with parking brake set.
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Unrelated question: why can't aviation be more simple? I know it sounds dumb at first but let's say tesla decides to re invent air travel and open airports with simple universal lights and approach systems beacons etc. And also rethink the plane maintaining safety and redundancy but more user friendly I guess. Seems like there's more three letter words and designations for stuff than you can shake a stick at and I sometimes wonder how much of it is repeated by having different words for things and standards and stuff and how much is really important or needed anyway we have so much technology nowadays that I don't understand why I can get in a plane and just fly would love a pilots opinion
@@francopetre6171 Perhaps, if you really want to find out, and not just expecting someone else to do the thinking for you, go to your local flight school, get a trial lesson, you will answer your own question as you climb past the runway edge on departure . . .
Two anecdotes from my days as ground crew..........
1) Mobile belt was left idling and uncrewed whilst waiting for a plane to arrive at the gate.
The gearlever didn't engage into PARK properly and managed to slip into drive (they vibrate a lot).
It took several seconds before anyone noticed that it had gone missing and then there was a scramble for anything that moved, to catch it (already crossing a live taxiway) before it hit a widebody parked on another terminal.
There was a daredevil leap onto it and the widebody was saved.
2) Aircraft just stopped at the gate, chocks going on.
Mobile belt already had the belt raised and was moving into position. The driver applied the brakes...nothing happened (a brake disc had fractured). The driver 'bravely' jumped overboard (no point having a steering wheel jammed into your gut) and the belt hit the aircraft.
It was an ATP - it was tired and wanted to sleep, so it let its tail droop sadly.
It stayed on the gate for a couple of days before being removed and fed to some chainsaws - I beleive that cost our insurers about £6.5 million (that was the figure bandied around the crew room - 6.5 for a leggy ATP? Maybe it grew whilst doing the rounds).
I had an alibi for both :-P
It just wanted a hug
That’s also possible
@@MentourPilot at what stage of pre-flight checks are you supposed to hug the aircraft?
who is responsible for it?
how long can a 737ng go without hugs? (i know it must not be supposed to happen, but maybe it's been crewed by unfriendly people for a few legs).
I can't believe those guys were trying to stop a 20 TON aircraft by pushing against it. It's like, are you kidding me with this shit?!
@@zloychechen5150 Perhaps she was lonely and wanted to be crewed between legs....
It's 2020, we all want a hug. But we can't...
I used to be a ramper for northwest airlines many years ago. One of the first things we do after the plane is parked and the beacons are turned off, the rampers would chalk all outer wheels and the nose wheel. Then give the signal to the crew wheels are chocked and free to release the parking brake.
The best one I heard was from years ago at one of the New York airports, the cleaners came into the terminal in early morning, to find a large jet sticking through the window, after it had rolled free, it was like a scene from Airplane.
The morning rush was starting in less than an hour, and the sight might have made some nervous flyers terrified.
However, when the crowds started to arrive, they saw a tidy 'exhibit', surrounded by every pot plant in the airport.
The aircraft was quietly removed that night....
That's next level clever!
Yo, that's slick af. Whoever came up with that idea better've gotten a sweet little bonus for that.
Bit more info, the ground crew removed the chocks about 45 mins previous to the aircraft starting to roll. I believe the plane was being prepped for return to the leasing company.
I don't work as a pilot or ground crew but I would have thought that the chocks should stay in place until either the plane is ready to move under its own power or is hooked up to a ground tug.
Absolutely sounds like something that must only be done once the commander confirms hydraulic pressure.
Is it not SOP that they would not be removed until the plane was just about to start rolling with a crew in the cockpit and the engines about to be started?
@@dmfraser1444 I would say *after* engine start to guarantee hydraulic pressure.
william Mitchell not so the D8-Q400 has a DC Hydraulic Pump that runs off the aircraft battery and ensures hydraulic pressure for the parking brake as well as providing other emergency functions.
@@andybashford8648 The DC Hydraulic Pump powers only the elevator, in a separate hydraulic system, as a backup in case one or both main hydraulic systems fail. It does not pressurise the parking brake.
Wow who knew aircraft did their own thing at nighttime?!
Yeah! They are naughty little beasts 😂
@@MentourPilot Like Toy Story.
This is how smol Cessnas are born ^^
@@MentourPilot little?!
@@NetAndyCz yeah sometimes they roll over to scratch their backs in the grass like a puppy in the sun.
Nothing says "it's my time off" like hammocking on the green screen, haha
Jakub Kamiński That's no green screen. That's his own garden in Girona. 😄
Cxar71 they’re talking about the hammock itself, it could double as a green screen!
Yeah! What can I say, when inspiration hits, it hits! 😂
Hey Mentour, you are absolutely right about the hydraulic hand pump. It can be used to increase pressure to the #2 hydraulic accumulator that supplies pressure to the parking brake. Sadly I don't believe this could be used under the circumstances, here are my thoughts:
Here's what would have to be done: Someone would have to enter the cockpit, ensure the parking brake is set, open the main gear doors using the manual alternate release handle, as the pump is accessed with the main gear doors open, remove the hand pump handle from the cockpit (it is the same used for alternate gear extension in case of hydraulic failure) and run out to engine 2 to operate the hand pump. This would increase the accumulator pressure and apply the parking brake, stopping the aircraft.
The problem is that the pump is too high to reach without a step ladder, or one could climb onto the wheel to reach it, but both these methods are not feasible with a plane rolling and in the time available. I don't see how even someone who knew exactly what needs to be done would be able to pull this off under the circumstances.
Here is some pure speculation: as you said, accumulator pressure decreases over time, so perhaps there was just enough pressure left to hold the aircraft still. If someone inadvertently, or without thinking it would matter, released the parking brake in the cockpit, that pressure would be lost, and even applying the parking brake again would have to effect, as the pressure in the accumulator would be depleted.
Parking brake left off / loss of hydraulic pressure and no chocks under the wheels. Basic aircraft ground handling.
In other words, somebody just fucked up.
I worked on an RAF base and they had a Harrier jump jet being washed, it rolled away and poked its nose through the door of the next hangar.After that they had chocks and a tug connected with a guy sitting in it.
Yes, that’s what tend to happen after incidents like this
'HEY GUYS WHAT IS GOING ON IN THIS HANGER'?
I was the aircraft washer on this Harrier jump jet. It happened on July the 23rd 2003. It had come into me for a backend wash. Which was from the tail fin to the rear nozzle. Job took me about half a hour once done I informed my supervisor that the jet was finished and ready for collection by the squadron who’s aircraft it was. I returned to my porta Kabin to await collection of the jet. Whilst having my break I heard a noise went to look and out the corner of my eye I saw the jet moving on it’s own it rolled of my pan across the road hit a cherry picker/access platform before sticking it’s nose to the outside of the hangar. It turned out following the investigation into the incident that the squadron had not put a enough air to the brakes and as a result with the aircraft started to slide on the cleaning fluid Gel and that started the aircraft on its journey. I have a couple of pictures of it on my instagram page halliday8995
I guess you could say that aircraft stuck it's nose into someplace it didn't belong.
Similar here, aircraft being towed out of the bay it was in. However there was miscommunication, and they did not disconnect the nose wheel steering link pin, so as the tug and the tow bar turned, the nose wheel did not. Frangible link did as intended, and broke, disconnecting the aircraft from the tow bar, and, as it was now on the slight incline out of the bay, it rolled down till it stopped in the reinforced earth berm 10m away. Guy in cockpit was pumping the brakes, but as there was no power, as battery was disconnected and removed, and he had no time to use the hand hydraulic pump either, so it rolled till stopped. Unfortunately the furtherest point forward was the pitot static tube, which pushed back, shearing it's mounting points, and moving back around a meter into the nose. Then the radome tip hit the wall, and penetrated the 3mm steel sheet.
Radome actually survived intact, no damage to it or the rest of the radar cover at all. Unfortunately not so for the pitot probe, and the space behind it, which was the main electrical control box for the aircraft, and the aluminium alloy probe pole sheared through it right in the middle, cutting the main mount that held all the aircraft relays almost in half, relays, wiring and breakers and all.
Damage was repaired in under 2 weeks, because there was another airframe undergoing a full rebuild, and that nose section was completed already in the rebuild, so it was shipped out, and put on in place of the original, which then went to have it's 7 figure rebuild, delaying the other aircraft only by around a month overall, but more than doubling the overhaul cost. That aircraft was odd till it's next major service, having 2 distinct different paint schemes on it front and rear.
There was quite a bit of fall out from that, but luckily I was a spectator, though did get to see all the carnage up close, as the radome came in for inspection, along with the nose of the aircraft landing up outside our service unit doors for a month.
Like in the movie “Airplane,” couldn’t they have just manually inflated the autopilot?
“I just want to tell you both, good luck, we’re all counting on ya.”
And please stop calling me Shirley
Looks like I picked the wrong week to quit smoking.
Roger, Roger
Looks like I picked the wrong week for sniffing glue
Look, there’s a sale at JCPenney!
Wheel chocks are CHEAP... take a 6X6, cut at diagonal to make triangular shape. Cut to desired length(s). Drill and add a rope for convenience. Paint the wood a bright color. (So the pilot can see that the chocks are in place as they board the aircraft instead of trying to power over them.)
Really low tech and highly effective.
Slope isn't really needed... wind can get it going.
Absolutely. Although, I wouldn't think that the (perceived?) cost of chocks was a factor to why this incident occurred.
@@hawk_7000 More likely they were in a hanger far away, and habit of "we never use them, it will only be here an hour at most" meant they were in the hanger still. I remember my erstwhile trainer coming in white as a sheet, because he was out flying, and they had a fire warning, so put down on the nearest thing to level, then the pilot kept the helicopter planted down hard, while all were out looking for suitable boulders to chock the wheels. Only when the wheels were suitably boulder impeded did he finally power down the engines, and pull the fire extinguisher handles to put out the fire burning up on the top, then they went up after rotor stop and put the remainder out.
Radio call came in for somebody to bring out the required hydraulic hoses, the tools to change them, torches, a lot of hydraulic fluid to fill the reservoir again, some cleaning material and something to drink. He left 07H30, and came in white as a sheet at 15H20, from what was to have been a 2 hour training flight. Next day fire bottles replaced, and the extinguisher sent in for service, and all the rest of the fleet had those same hoses checked, and a month later all new PTFE stainless steel braid reinforced hoses installed in place of the original rubber. Took a day to wash that oil off the chopper, it was literally in every panel and compartment, along with the soot.
F Huber - But you disembark and board with chocks in place. It is rare for aircraft on any apron not to have chocks.
Peter, I've been called "micklin" after the character on "blscksheep squadron" for years. Your technical videos further my lifelong interest in the mechanics in aircraft. Thank you so much and keep up the good work!!!!
so glad no one hurt. its like having a great big trucks brake fail a lot of mass and once rolling hard to stop.
The Flybe Q400 just wanted to be a metaphor for Flybe’s economic demise. Rolling away out of control and then coming to a smashing halt. Poor Flybe.
And wasn't Loganair to take over some of their destinations?
Or was it an insurance job?
Certainly the payout might be useful for the creditors...
🤣🤣🤣🤣
1:40 They were actually putting themselves in a potentially dangerous position by standing in front of the wheels whilst it rolled.
One slip and they would have been crushed.
Don’t forget to lace your chocks. Working at Hill Air Force Base on F-4s in the late 70s. Our pro super was always telling us to lace the chocks, thought he was just busting our chops and wanted the flight line to look tidy. Well it rain one day so hard that I saw some of the chocks flot away down the ramp
When your dog began barking the first thing I thought of was the “barking dog” hydraulic sound that is heard on Airbuses! 🐕 ✈️
😆😆😆😆
Lol! A furry PTU!
Pilots are choosing dog, based on this.
The video is up there, really deserves a David Attenborough voice over. 'Here we see Aircraft in their natural environment, they assess each other and move cautiously for a closer inspection etc'.
I used to work at an airport and every morning we would tow a plane that had been sitting in remote parking overnight and by that time there was usually barely any hydraulic pressure left. So before towing we would always start the APU so we could pressurize the brakes (among other reasons).
I am retired from the railway where I was a train driver. We had the same problem where the loco brakes relied on compressed air and the handbrakes were sometimes dodgy. If a loco was parked on a gradient for any length of time it was possible for the compressed air to leak away, the handbrake fail and I can tell you that when 149 tons of loco starts to move on its own it will take a lot of stopping.
Earlier today, I had watched a fascinating video where they ground tested each engine while attached to the jet. The chocks used were absolutely huge, and when each engine was throttled up one at a time which resulted in the whole jet vibrating. Just sharing that that was amazing to watch. I didn't know that they tested each engine full throttle on the ground.
I enjoyed your video today very much too. I agree that the chocks are very important to use. Take care!
I used to work at Phoenix Sky Harbor Airport, they had a place called Dynair that refurbishes Jets and does maintenance. I remember listening to the run up on a DC-10, alot of smoke at first then you could feel the Earth move when they throttled that up.
@@jasoncentore1830 Hey PHX! Yep, back in the day. Was that before, or after SabreTech owned the hangar? SabreTech ceased to exist after their Florida operation contributed heavily to the ValuJet 592 crash.
Watch the tail of an Antonov 225 twist from the jet wash as the thing throttles up.
The airplane just awaken it's canine instinct and went to have a sniff into the rear of the other airplane 🐶😅
It stuck it's nose where it didn't belong.
It went to sniff its APU exhaust!
😂🤔😂
Yep, comment of the day goes to Johnny Chang!
😆😂🤣
Dog barks when you talk about hydraulic system.
A320 is calling you.
Just amazing. In all my flights, I have never seen a commercial plane temporarily park at a gate where the very, very first thing done was not chocking the wheels. The ramp crews ALWAYS put those in place first thing. I cannot recall a single flight where I did not see this done, even for very short turnarounds. I am just astounded that this was not done.
Something as dangerous as an aircraft not being secured is really negligent.
This video brings back memories. My car was the victim of a "no humans involved" crash in a parking lot when the other vehicle didn't have the parking brake set. I've chosen the high ground for parking ever since!
Never a full Scottish football team around when you want it.
B.Raff Celtic FC,Big jock knew,,
So now we know what the Scottish football team is good for, as it isn't football LOL
😃😃😃
You'd need a rugby team, not a football team. Those football hairdresser fillers couldn't stop a fart 😂
@@imaner76 I'd have suggested an American football team, but rugby is pretty close.
Greetings from Asunción Paraguay
It's also kinda windy up here in Aberdeen - cue the rest of the world (incl. England) googling where Aberdeen is
The parking brake was my superchat question a couple weeks back
Most relaxed Petter ever. ;-)
Thank you for the information!
This makes me laugh because it recalls an incident in my own business. I worked in France on canal hire boats. We had an enormous amount of damage at the rear of our boats and had to suppress a feature because of it. Our boss kept telling us about how great the boats in another region were and how they never had any damage. One day a lorry delivered a boat from the said region and it was craned into the water. As the driver was in the office signing the paperwork, I heard a noise and the brakes on the lorry gave way. It ran backwards and smashed the part of the boat we had to repair on our own. 10 minutes and the damage was done. ;-D))
Respect the machine! Very well said.
Murphy's Law: If it can go wrong, it will.
No, not Murphy's law this time. Now its McDougall's law
This was pure negligence. Nothing on the aircraft failed. Any hydraulic system will leak slowly without pump pressure.
That's why the railroad cars brakes when the pressure is lost. Same with air brakes on trucks, so when the pressure is lost and it has to be towed then the air bells have to be "caged".
@@ehsnils Nonsense. Big trucks have spring brakes that holds it in place. When air pressure is lost, the brakes stay on.
Don't argue please, I'm a mechanic and drive buses and 18 wheelers.
In England it's Sod's Law. Don't know if they use that phrase in Scotland.
The big Sprinter van I drove for work slipped out of gear after I parked it at 4am and rolled into me as I was walking in front of it towards my coworkers house on the opposite side of the street to drop the keys in her mailbox. It pinned me against the vehicle parked in front of it. The street had an incline and that's why it rolled forward and into me. My cellphone was in my back pocket and I couldn't reach it. Nobody was on the street at that hour. I was really crushed and pinned tightly. I felt like I was going to go into shock. All I can remember after that was getting determined to free myself. I don't know how I pushed that big van back uphill but I did, and I wiggled out and temporarily lost consciousness when my blood flow was adjusting. I have very low blood pressure. I weighed about 110 lbs at the time. I was black and blue and deep purple for weeks on the lower half of my body.
4:46 omg that doggy bark was so perfectly synced with your speech :D
I used to do line maintenance on those aircraft. Pumping the brake accumulator with the black and yellow pole take about 10 minutes and won't be achievable in that situation.
Loved it! I was wondering how that incident happened. Thanks for clearing that question.
What's interesting is that I read an article earlier in the week that said there were two pilots on board who were taxiing and crashed into the other plane. Which kind of explains modern media today. "Hear about an incident, make up our own details, and report it as fact."
Erm they didn't secure the aircraft ....
The hand pump is in the right MLG bay. It pressurises the parking brake accumulator and nothing else. If my memory serves me, you have to release the hydraulically operated gear doors (the Q400 has two sets, FWD "mechanical" that remain open after extension and AFT "hydraulicaly operated" that close) to get at it. If I remember correctly, if the brake lever is set cranking that pump should pressurise the brakes. The trick is to get at the handle, it's mounted pretty high in the bay. You have to remove it from the bulkhead and insert it in to the socket in the pump. I'd say the chances of someone opening the doors, removing the handle and cranking up enough pressure for the breaks to bite as the aircraft is moving is... ZERO.
Thanks! This is very important. Every aircraft should be chocked or tied down after every flight!
Great question! My 13 year old Toyota Corolla hand break has needed adjustment for about 10 years. I need some chocks!
FYI, the Dash 8 is formally known as the De Havilland Canada Dash 8 Q400. Bombardier sold the whole aircraft program to Longview Aviation Capital Corporation in 2018, and the deal closed in mid 2019. Longview revived the De Havilland name to brand the aircraft.
Just find myself watching each and every mentour's videos..
Thank you for saying "there is no system that is perfect" in reference to fluid systems. I had a guy hounding me for a few days when I mentioned that same concept in reference to fuel systems and acceptable amounts of leakage.
I tried explaining, but he cited all sorts of qualifications he had earned, called me some pretty radio-unfriendly things and told me if he ever found me he would report me. haha.
Your insight is always appreciated. Cya round 👊😎
There's nothing more ironic than someone using their qualifications to try to hold a position that is so obviously wrong. It's like they're trying to prove that those credentials aren't worth the paper they're printed on.
Interesting info. I’ve learnt a lot from the first day I’ve discovered your channel
Thanks for your clear explanation.
The fact that he's not uploading that much is a good sign😍
7:34 I thought he was going to say absolutely fanstastic
Totally nailed the ending with Paxi! :)
The video of the crash at Aberdeen is still on RUclips. ITV news ran a report about the crash three days ago.
“Hydraulic pressure leaks out” trucks laugh in air brakes”
As a truck driver I love this comment.
Who knew that trucking would outshine aviation 😅
I've seen more than a few light planes where there is a set of chocks in the back so when you park somewhere you can secure the aircraft if there is not a tiedown
A follow-up question: what about parked planes during a very strong wind situation?
Swiss Surfer - In strong and gusty winds aircraft are turned nose into wind and, where possible a tow bar attached to the nose landing gear and a tug attached to the tow bar. This helps to prevent the aircraft from ‘weather-vaning’; ie: literally swinging round.
If the CCTV video was in better resolution it could be a really good meme for how a plane is born.
Rough day at the office I see.
On a Semi tractor trailer (lorry), the brakes are spring loaded and always engaged, and requires about 110-120 p.s.i. of pneumatic pressure from the tractor in order to release them so it will roll.
I just watched the cctv footage. So still in circulation. Thanks for answering my question about how it happened.
Outstanding explanation!!!
It's still out there and just watched it.
Great video
Thank you! Glad you liked it!
And when you release the brakes onto the chocks, it can wedge the chocks in there good! I had on one occasion, the need to hammer the aft nose chock out with the forward chock and the whole CRJ200 dropped when it finally broke loose! Marshaller said the pilots were a little shaken!
My stepdaughter had to do that multiple times on an A-320, she said you should see the pilots face when she came around the corner with a sledgehammer draped on her shoulder, for some reason Pilots hate when you have to beat up on there plane with a hammer
@@jasoncentore1830 Maybe the airport authority should put a little more attention into leveling the apron?
Surely then you’d just get the pushback tug to push or pull the aircraft a bit. It can only be seized on the front or back
Petter, I wonder whether it was windy that day? Tie downs work wonders on smaller aircraft!
Awesome video Mentour have you ever been to Aberdeen?
No, I haven’t had the pleasure yet
Mentour Pilot It’s a lovely place hopefully you’ll get to visit
Cool! Question: does the number of wheels that have to be chocked increase with even bigger aircraft (with more wheels)? Keep up the absolutely fantastic work!
I've worked on a pretty large aircraft in the past (C-17.) Only ever needed chocks on 2 wheels
Tends to be weather related more than size. where I work, we'll chock the final set of gear when the wind exceeds 20mph sustained.
I have a question for a future video please... during COVID obviously fewer planes are flying. Are planes ‘rotated’ across the routes that are running to ensure they all get used a little, or are some of them basically mothballed until needed. If they are mothballed, what additional checks, if any, are undertaken before the plane is put back into service? What could go wrong because they have been ‘sitting’? I’m not asking as a nervous flyer by the way, just interested. My car feels ‘different’ after just a few weeks of not being used.
Thanks. You do fascinating videos even to someone like me who isn’t in aviation at all.
Love the hammock lol
he should do all videos for now on in the hammock
Starboard hammock...
Seals it. Logan should buy Flybe
Can you make a video about what makes high altitude landings challenging?
Damn.. you're not allowed to park even semi trailers without wedges in Finland. And those trailers have *brakes that lock by removing pressure* meaning only way to release the brake is to re-pressurize the system. Why would you ever park a plane without chocks?
I remember a couple of months ago where something similar happened between a Qatar Airways 787 and A350. It's really sad how people went out of their way to blame Boeing for that.
The major reason for static hydraulic systems to lose pressure is due to thermal expansion. When ambient temperature increased this causes an increase of pressure in the hydraulic system then the overpressure relief valves open and let this excess pressure out. When ambient temperature decrease there is a corresponding drop of pressure in the system.
We as humans will never fully understand aircraft attraction and mating rituals.
That's interesting. In a tractor trailer, you need pressure to RELEASE the brakes. With no pressure, the spring will just hold the brakes locked until the driver applies air pressure. The only time we chock wheels are during repairs, or when the company has an engine cutoff in the truck, so the driver will override the cutoff by releasing his brakes and chocking the wheels.
I worked for 2 airlines - American and United Express ( Westair - contract carrier) as a Ramp agent and even as the push back tug was hooked up to the aircraft the nose gear and main gear stayed chocked
4:40, Mentour talks about hydraulics. PTU starts barking in the background
I work for a railroad and we handbrake and chock the wheels too. However we have had runaways too. Usually a defective hand brake.
Those ramp rats should have verified the aircraft was chocked and grounded before touching it. It’s the first step in every maintenance checklist I’ve seen.
Not a slope - ABZ is usually really windy as it’s by the North Sea. The panicked workers trying to push it made me chuckle, but they also put themselves in danger.
Nice bonus video for me
4:53 dogs may be off screen but they still want to be part of the entertainment
This is indeed a strange phenomenon. I used to drive 18 wheelers, and you can stop on a level surface, not apply the handbrake, and the vehicle can start rolling after standing still for hours.
Very strange, and a reminder that it's best to double check the park brake is properly set.
I suppose the problem just becomes more tricky for heavy vehicles, with all that inertia... Both the "sneaky" start of the roll and then taking a lot to stop once they get going.
@@hawk_7000 Yes. Very sneaky how they start rolling.
I appreciate the ground workers wanting to stop it, but that isn't wise. I once watched a truck driver run over himself with his own truck. He didn't set the parking brake, and it started to roll. He grabbed a set of drive tires to try to stop it. He got pulled under, and crushed his legs. If he just let it go, it would have crashed into a nearby wall and taken damage, but he would be walking.
I ran over from my truck, got it in gear and moved it off him, called an ambulance, and took care of him the best I could until the paramedics got there.
I'm satisfied that I did what could be done, and don't question my own actions after the fact. But.... When it was over, I puked so hard my belly was sore the rest of the day. Years later, I still vividly remember his screaming.
Engineer: "This is just like the e-brake on a car."
The Brakes: "Can't. Hold. On. Much. Longer!"
Thanks for good info
Great video. I love how you explain these things in such detail, it is only here on your channel that it is possible to really learn these technical details. A thing such as the parking brake on the 737, I always assumed it would be a separate braking system. I hope to be a 737 pilot after university and I’ve learned a tonne from you. Thank you Petter :) Chris
...and don't drink whisky before you secure the chocks....
Fun fact, the chocks have also caused a 737 emergency landing too... In flight Piedmont Airlines Flight 1489
The poor captain was unable to lower the landing gear as the chocks were stowed improperly in the well and slid in to block the extension of the gear.
After inducing some Gs he was able to shake lose one of the gears, but had to use the engine cowling for the other.
Did you see that crazy runway excursion at BHX Petter? On flugsnug channel.
No! Do you have a link? Did it just happen?
Big truck brakes are very different. Parking is by mechanical spring.
Talking about737 800 Still have pulleys and cables in case of hydraulic sys failure ?
I’ve asked this question before and if there was an answer I missed it, apologies if so. Why not use the road transport “spring release” parking brake, albeit a beefed up version. Ergo with no system pressure the wheels are locked by the spring pressure.
Weight, plus the reason they're fitted to trucks (in case of catastrophic air loss) is more likely than that you get a rogue activation of a spring brake. While extremely rare rogue activation can happen & the resulting skid is dangerous & spectacular if it happens when moving, the consequences of such a rogue activation on an airliner during takeoff or landing don't bear thinking of, they come on on one setting (full) & being a dumb mechanical system can't incorporate anti-skid or ABS. Aircraft already have multiple hydraulic systems to mitigate the failure of one, & thrust reversers as an alternate to brakes on landing if brakes should fail.
Secondly, chocks provide visual confirmation to ground crew that the aircraft is secure, in haulage & transport generally drivers forgetting to set the parking brake isn't as uncommon as everyone would like & the only way you'll know the vehicle isn't secure is when it moves long before the air bled down enough for the spring brake to activate, all too frequently causing injury in addition to damage.
Finally spring brakes can themselves fail (broken spring, corrosion, seizure) without any visual indication it has happened, chocks don't suffer from those problems. The potential failures are not using them (obvious to everyone), using chocks that are the wrong size (typically too small, also apparent to anyone passing) and chocks slipping on ice/spills/poor surfaces etc. In these days of not being able to rely on common sense & lawsuits about everything, that means training for people setting them.
Technically I've little doubt such a spring backed parking brake system could be engineered along with a system to prevent activation at dangerous moments, it would be expensive to do, probably more so to certify, would add to operating costs both through another system to inspect & maintain plus the cost of carrying the weight, I doubt it would be mandated unless there's a serious accident chocks wouldn't have prevented first.
The failures here were to set chocks, & train work crews that they should check for them being set.
Fun fact: If a haulage company expects to stand trucks or trailers for an extended period of say weeks or months, especially in winter, they'll often use chocks & store the vehicle/trailer with brakes off and spring brakes disabled to prevent them locking or freezing on.
hi Mentour, have you seen the film 7500 just released by Amazon? it is entirely shot in an (Airbus?) Cockpit, I would be curious to hear your review! :) I guess the title gives you quite some hint as to what it is about!
I may be wrong, but my instinct would have been to get in to the seat and use the nose wheel staring turn left or right to counter the incline. Would that have worked? Or would the lack of hydraulic pressure been an issue?
No hyds unfortunately, you may have got a few degrees
I'm a truck driver and we use (pneumatic) pressure to RELEASE the parking break, not set it, just to avoid situations like this from happening. Do you know why airplanes are not designed in a similar way?
Means building in another system that requires monitoring, redundancy and maintenance. Just easier to chock the aircraft
Had no trouble finding the Aberdeen video on YT.
I dont know about the q400 but the 737 has a brake accumulator that is charger with nitrogen which is around 1500-1800 psi that holds the brake pressure when the hydraulic pressure is not available. However a bad accumulator bleeds the nitrogen and the brake will be less effective and if the chokes are not there it will roll with parking brake set.
4:50 So your dogs actually bark😂😂
Great video thanks!! Were the dogs barking to get in the hammock?