Excellent video showing a tail wind start where the fan is initially windmilling backwards. Eventually, the airflow induced by the starter's rotation of the core IP spool creates enough airflow through the core to get the fan rotating in the correct direction which is clockwise when viewed from the front on Rolls-Royce engines. Well done Ramper Ryan ... (RR)!!
@@UNITED38Heavy Correct … the core spool is cranked electrically by the engine gearbox mounted generator acting as a starter motor in the start phase. After engine start it supplies electrical power to the aircraft … some of which is used for driving the cabin air system … no engine bleed air off takes … ingenious!
@@ohnezuckerohnefett This engine has three independent rotating shafts comprised of the fan (also called the LP or Low Pressure system) and its turbine … the IP or Intermediate Pressure system and the HP or High Pressure system. The wind acting on the large fan can turn the LP spool but there is not enough airflow through the core of the engine to turn the heavy IP and HP spools so no problem for the starter drive because it’s connected to the IP spool. Starting the engine in flight can be a different case because at most airspeeds there is enough airflow through the core section of the engine to induce rotation of the IP and HP spools. If the airspeed is high enough, the engine can be lit up and brought to idle without using the starter (aka the Variable Frequency Starter Generator VFSG)! ✈️😄
Yep, it used to be a real problem on the lower bypass engines like the JT8D, we would have to engage the reverse buckets until we put the fuel in or it would hot start like an SOB.
When the fan is windmilling backwards like that, how does it register on the engine instruments? Positive N1, negative N1, or is it too slow to register at all?
Rotor speed is typically measured by a sensor adjacent to a multi toothed wheel (phonic wheel) that is mounted on the rotor shaft where the frequency of tooth passage is converted to rpm and usually displayed as a percentage value where 100% equals one specific rotor speed. The output from the sensor is the same regardless of the direction of rotation of the shaft so a fan rotor that is turning backwards displays as a positive value in the cockpit. When the starter turns the core spool, the induced airflow starts to slow the windmilling fan until the indication drops to zero percent and then starts to rise as the fan speed increases in the correct direction. Engine light up on start is delayed until there is positive rotation on the fan.
To shorten what^he said, it shows a value. (Might be too slow a windwill to actually show a value in this case but thats just a guess) And it still shows positive. Doesnt matter which direction it spins.
A fan rotates in the opposite or negative direction when there is a tailwind on ground starts. This tailwind is acting on the rear surface of the fan blades which creates the torque to turn the fan rotor backwards. If the wind is blowing from the front of the engine, then the fan will turn in the correct direction. It follows then that any time an engine is not running in flight, the fan will be windmilling in the correct direction because of the airflow through the engine inlet.
@@mrmylo1239 Fun fact ... Rolls-Royce have used the name Trent for three different engines ... the RB50 (world's first turboprop in the 1940's), RB203 (world's first three shaft turbofan in the 1960's) and of course the current familly of large civil turbofans! Rolls-Royce name their aero jet engines after rivers where the continuous, uninterupted flow of water is a good analogy for the working cycle of a jet engine. One notable exception to this naming convention was the classic RB211 when it was decided to not name the engine which was offered for the L1011. Subsequent variants of this engine for the B757, B767 and B747 weren't named either. The closest we get to a name reference on these engines is the RB211-524G/H-T (B767 and B747) where the T stands for, you guessed it ... Trent! That engine incorporated the complete High Pressure module of the Trent 700. ✈🙂
I don't know anything about these engines but I figured that heat behind the engine initially was from the bleed air that is being used to get the engine initially spinning before it's lit.
In most aircraft there's an air turbine starter. High pressure pneumatic air from APU or ground supply (or in extreme case, from the other engine) spins up the starter, which turns the HP shaft via the accessory gearbox. The 787 doesn't have a pneumatic system. Instead, its engines' electrical generators (variable frequency starter-generator, VFSG) also act as starter motors. During engine start, electrical power from the APU is sent to the 2 VFSGs which spins up the HP shaft via the accessory gearbox. Once the engines are started, the VFSG start generate power for the aircraft. If there's no APU available, a 3rd external power cable is plugged in the aircraft for the engine start.
Saya berasa puashati kerana menjadi sebahagian dari krew yang terlibat dalam pembuatan Fan Case (pemesinan dan pemasangan) sebelum ia menjadi sebuah enjin T1000-Ten yang canggih.
For the 787, GE is more popular. RR has had some reliability issues in the last few years but it's mostly resolved now. Personally I prefer RR in terms of maintenance.
No, the fan blades actually stopped and started spinning in the other direction. Someone in the comment section explained what's going on better than me though.
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Excellent video showing a tail wind start where the fan is initially windmilling backwards. Eventually, the airflow induced by the starter's rotation of the core IP spool creates enough airflow through the core to get the fan rotating in the correct direction which is clockwise when viewed from the front on Rolls-Royce engines. Well done Ramper Ryan ... (RR)!!
The Dreamliner doesn’t have bleed air if I’m not mistaken, everything is done electrically including engine start.
@@UNITED38Heavy Correct … the core spool is cranked electrically by the engine gearbox mounted generator acting as a starter motor in the start phase. After engine start it supplies electrical power to the aircraft … some of which is used for driving the cabin air system … no engine bleed air off takes … ingenious!
So is there a brake for such situations? I imagine you can't just turn the electric motor on, that might damage the gear of the starter?
@@ohnezuckerohnefett This engine has three independent rotating shafts comprised of the fan (also called the LP or Low Pressure system) and its turbine … the IP or Intermediate Pressure system and the HP or High Pressure system. The wind acting on the large fan can turn the LP spool but there is not enough airflow through the core of the engine to turn the heavy IP and HP spools so no problem for the starter drive because it’s connected to the IP spool. Starting the engine in flight can be a different case because at most airspeeds there is enough airflow through the core section of the engine to induce rotation of the IP and HP spools. If the airspeed is high enough, the engine can be lit up and brought to idle without using the starter (aka the Variable Frequency Starter Generator VFSG)! ✈️😄
Yep, it used to be a real problem on the lower bypass engines like the JT8D, we would have to engage the reverse buckets until we put the fuel in or it would hot start like an SOB.
Thank you for all mechanics working hard to make sure the plane is safe to fly!
These engines are masterpieces of engineering.
Yep, with the engines on a 787 putting out more thrust as 2 Boeing 707s while using significantly less fuel.
@@michaelmurray7199not as much thrust as 2 707s, but still alot more than 1
That SpeedBird pilot wasn't kidding, Rolls Royce engines have a deliciously beautiful startup sound.
We saw the same video, and had to wonder what he meant. He was right. That is a low rumble coming alive.
Pause it anywhere and there is a perfect freeze. What is that frame rate. WOW!
It's all about shutter angle. The sun is out and shining, so the camera only exposes a very short time window within in each frame :)
> 5000m3 per second. 5000 cubic meters of air passes through that engine every second at 100% power.
5,000 m³ can be a lot or a little bit of air depending on air pressure.
so, like a Dyson?
@@Man0fMeans More like 1,000 Dysons, maybe 10,000.
Great for filling baloons
Nice Trent 1000 ❤❤😊😊
Interestingly, or not, some of the internal parts of the engine operate at temperatures higher than their melting point. 😮
When the fan is windmilling backwards like that, how does it register on the engine instruments? Positive N1, negative N1, or is it too slow to register at all?
It’s off, not running, so it isn’t showing anything registered on the screen. Once they fire it up, it comes alive
good quesion though
Rotor speed is typically measured by a sensor adjacent to a multi toothed wheel (phonic wheel) that is mounted on the rotor shaft where the frequency of tooth passage is converted to rpm and usually displayed as a percentage value where 100% equals one specific rotor speed. The output from the sensor is the same regardless of the direction of rotation of the shaft so a fan rotor that is turning backwards displays as a positive value in the cockpit. When the starter turns the core spool, the induced airflow starts to slow the windmilling fan until the indication drops to zero percent and then starts to rise as the fan speed increases in the correct direction. Engine light up on start is delayed until there is positive rotation on the fan.
To shorten what^he said, it shows a value. (Might be too slow a windwill to actually show a value in this case but thats just a guess)
And it still shows positive. Doesnt matter which direction it spins.
محرك ضخم ويعيد عن مركز ثقل الطائرة؟! وكأن من صممها يريد أن يرتكب جرائم تسلسلية تقنية للغاية ، أليس كذلك؟!
Looks and sounds like the sounds were coming from another engine LOL
Great video.
You should get closer to give us a better view
😈
I think he was close enough.
Is this 787
Why does the fan rotate in the opposite direction before the engine starts up?
Because the wind is spinning it in that direction. Its called wind milling
A fan rotates in the opposite or negative direction when there is a tailwind on ground starts. This tailwind is acting on the rear surface of the fan blades which creates the torque to turn the fan rotor backwards. If the wind is blowing from the front of the engine, then the fan will turn in the correct direction. It follows then that any time an engine is not running in flight, the fan will be windmilling in the correct direction because of the airflow through the engine inlet.
What is the tube with the smoke under the engine?
Looks like an exit vent for the compressed air used to spin it up before introducing the fuel.
I’m a proud English mann who lives 2 miles away from the source of the river Trent
Why even comment this
@@ramperryan because i live by the river trent the best engine ever 😛😛😛
@@mrmylo1239 Fun fact ... Rolls-Royce have used the name Trent for three different engines ... the RB50 (world's first turboprop in the 1940's), RB203 (world's first three shaft turbofan in the 1960's) and of course the current familly of large civil turbofans! Rolls-Royce name their aero jet engines after rivers where the continuous, uninterupted flow of water is a good analogy for the working cycle of a jet engine. One notable exception to this naming convention was the classic RB211 when it was decided to not name the engine which was offered for the L1011. Subsequent variants of this engine for the B757, B767 and B747 weren't named either. The closest we get to a name reference on these engines is the RB211-524G/H-T (B767 and B747) where the T stands for, you guessed it ... Trent! That engine incorporated the complete High Pressure module of the Trent 700. ✈🙂
That’s base at 0:50 😮
Cómo asen para Aser esa raya q de vuelta tan lento en velocidad emrnsa
What is amazing is the heat produced from the compression with just 1 full rotation of the front fan blade.
I don't know anything about these engines but I figured that heat behind the engine initially was from the bleed air that is being used to get the engine initially spinning before it's lit.
what a melody for my ears!!!!
Cool Video, thanks!
listen to this with heaphones
Is this an A350 airplane?
Sounds like Airwolf!
can words describe this?
Now, that is completely badass!
You're getting sleepy...
Acaso ponen puntos no creo
"N1 change direction tell me" - cockpit.
Nice 🔥
Look how low to the ground this engine is - AND they grounded Concorde!!!! - Bonkers.
How does the electric start work? Is it gear connected or blows air across the turbine section?
In most aircraft there's an air turbine starter. High pressure pneumatic air from APU or ground supply (or in extreme case, from the other engine) spins up the starter, which turns the HP shaft via the accessory gearbox.
The 787 doesn't have a pneumatic system. Instead, its engines' electrical generators (variable frequency starter-generator, VFSG) also act as starter motors. During engine start, electrical power from the APU is sent to the 2 VFSGs which spins up the HP shaft via the accessory gearbox. Once the engines are started, the VFSG start generate power for the aircraft.
If there's no APU available, a 3rd external power cable is plugged in the aircraft for the engine start.
Very nice
I swear I almost got hypnotized watching the center of the turbine. 😂
Crazy how many times it appears to stop or change direction.
video games
Fun fact: Your ceiling fans weigh less when they are running
Did it start? Why is it moving fwd and then bkwd and then fwd?
😵💫😵💫😵💫😵💫😵💫😵💫
Love the sound. The sound of holidays
What’s the alarm sound at 1:44 ?
Taxi way corssing alarm sound. Their was a A330 taxing by when I recorded that sound
@@ramperryan thanks!
Saya berasa puashati kerana menjadi sebahagian dari krew yang terlibat dalam pembuatan Fan Case (pemesinan dan pemasangan) sebelum ia menjadi sebuah enjin T1000-Ten yang canggih.
JFS...how is it started? cartridge start or hydraulic start?
Really sounds like the B-52 Cartridge start.
air from apu
😂
Ok 🤷♂️
I thought T1000 uses elelctric starter, how come this startup sounded like bleed air is used?
Where did you hear bleed air? No such thing could be heard.
Ignition happens at 0:45.
Qatar Airways is fine for me ❤❤❤❤❤❤❤❤❤❤❤❤❤❤❤
my scientific understanding of this world went into existential crisis for once when the propeller was acting as turbine in the start 😅
Go GE or take a bus ...
Im sorry who powers the A350 an aircraft that completely beats the American made Boeing 787??? Oh yeah Rolls Royce dose 😂
What engine is better ? RR or GE ?
For the 787, GE is more popular. RR has had some reliability issues in the last few years but it's mostly resolved now. Personally I prefer RR in terms of maintenance.
@@yatsumleung8618 thanks
Pratt & Whitney
The appearance of the fan blade stopping @ :56 and 1:11 is caused by the camera rolling shutter speed\effect, right?
Yeah, the rotation matches the frame rate so it appears stationary.
yeah the white bit in the middle is still spinning
No, the fan blades actually stopped and started spinning in the other direction. Someone in the comment section explained what's going on better than me though.
I believe if the engine was already on then that would be the case though
Are engines just allowed to "windmill?" There's no caliper or anything inside to lock them while parked?
Nope