You should have done an airfield tour, there's a few things of interest at Damyns. The Tiger Club is based there, and they also operate the Pipistrel Electro from there. The little cafe is nice too!
I did what amounts to a double major in both aviation and computer science. This was back in 2000, but I wrote my own flight calculation software for weight and balance and performance calculations. It was a ton of fun working through the maths to do all these calculations in the software such that I didn't have to fudge things on a graph. Thanks for the video!
This is another example of your professionalism and care for doing it 'right!' Well done. BTW I'm jealous of all those lovely grass airports (or should I say aerodromes? ;-) ) you seem to have at your disposal. I love getting my little Piper T-Hawk off the pavement now and then. It takes me back, I guess. Cheers and thanks again for posting.
A very good performance video that brings out the issues with paper performance charts, I have long thought an iPad app was needed for GA after using the Boeing Laptop tool for performance calculation on larger aircraft. What does concern me a little is the assumption that the aircraft will meet the flight manual numbers, back in the days before EASA the U.K. CAA required a flight test with an approved pilot to be done at each CofA renewal ( roughly similar to todays ARC ) . This flight test required quite a detailed investigation of the aircraft performance , quite a number of aircraft failed to meet the FM numbers and if the problem could not be rectified a performance write down was put in the aircraft flight manual. Add to this the fact told to me by a very well respected engine overhaul shop owner ( sadly long gone ) who for interest put a 200 HP engine that had reached TBO on his engine test bed, the engine made just over 180HP at full throttle. This all goes to show that the Factors that the CAA recommend are added to the FM performance calculation should IMO considered MANDATORY.
remember the rules about how much head/tailwind you can take - those factors came up with my examiner during the brief (and I dont think you can do the ground roll only for comm ops)
It's a POH/AFM checklist item. You switch to your fullest tank for approach. "APPROACH AND LANDING: Check to insure the fuel selector is on the proper (fullest) tank." I follow the POH.
@@TheFlyingReporter yup emailed yesterday and they would like me to send them the flight manual in pdf format, so fingers crossed they’ll add our old banger to the list!
Firstly. Whilst I congratulate John on producing his videos with good intent I would be much happier if he ensured that his productions were first over seen by a qualified flying instructor before publishing. The number of airmanship issues and questionable points that each one raises worries me that less experienced pilots might feel that his videos are AOPA approved as best recommended practice. On this I one I note the following: 1. John is right to say that the only graphs applicable for an aircraft are those in your particular POH or user manual. However, in the case of several aircraft there are supplementary sections supplied by the CAA at the time of certification that make the performance chapter supplied by the manufacturer invalid. In the case of the Archer the FAA manual (and graphs) are in VB790. However the CAA published supplementary take off and landing graphs in VB737 which override the Piper ones. John should have been using those if his Arrow has a similar CAA supplement. 2. I stand to be corrected but if a performance graph only shows ISA beginning at sea level then extrapolation below that is not allowed. Using -300’ is not an approved way to use the graph. 3. Whilst John adds the CAA factor for grass and a ‘fudge factor’ for take-off to 50’ he ignores both on the subsequent discussions regarding landing roll. If that landing had been on wet grass the result might well not have turned out so well. Note the advertised tablet app also only deals with hard paved surfaces.
4. John mentions slope but then ignores it in all calculations. To be fair, unlike higher performance aircraft slope is not easily available for GA pilots. However, the CAA recommend applying a factor of 10% for every two per cent of gradient (Skyway Code page 51). So how can you calculate slope when it’s not published? One method is to utilise Google Earth Pro and run a cursor from one end of the proposed runway to the opposite end. Reading the elevation shown on the lower right side of the map, the difference between each end can be noted. Dividing the elevation difference by the length and multiplying by 100 will show the runways overall slope in percentage which can then be used to apply a safety factor. This is particularly useful for farm strips and unlicenced fields. From the airmanship aspect I also would urge people not to change tanks at low level and near the circuit. Any interruption in fuel flow will occur at the worst possible time and be a major distraction. Also, the use of one stage of flap before or upon entering a circuit is unnecessary on a light aircraft. Along with the early use of gear both introduce speed limitations and distractions that result in reduced lookout and concentration. Gear on the downwind leg and taking the flaps on base is fine for any PA28. Otherwise I thank John for taking the time to make his productions.
HI David. Thanks for the comments. I do think you might be overplaying this. If it's any reassurance to you, the video was shared with a Flight Instructor prior to publication - they watched it three times and didn't find any fault. It was then shared with my supporter community, which includes examiners and instructors. No comment was made. For the avoidance of doubt, the videos aren't AOPA approved - AOPA is an advertiser. On your numbered points... 1. The charts I use are the ones in my POH. I don't have a supplement, especially not any for the Archer, as I fly an arrow. The charts in my POH are identical to those in the app. I gave a caveat about use of the app. 2. Your second point is noted, and you may be correct. If you have a reference for this, please do send it over, because I've not found chapter and verse on this from a manufacturer/regulatory point of view. There is nothing in my POH as far as I can tell, that says I can interpolate 300 feet above SL, but not 300 feet below it. 3. I didn't discuss wet grass, snow, long grass, soft field etc, because none was applicable that day. 4. The slope was factored into my take off run as it's applicable but the detailed take off performance calculations were not shown/demonstrated in the video. The calculations demonstrated and detailed in the video related to the landing, which had an upslope. There is no CAA factor for an upslope, and so none was factored in. Any upslope would help a landing, not hinder it. 5. The fuel was switched at A1700, over the QE2 bridge, four miles from the airfield. I do not judge this to be unsafe - certainly not anymore unsafe than A1700 10 miles from the airfield. 6. I'm happy with the timing of my gear/flap selection. Flap was selected on base - editing may have condensed this sequence - I just checked the raw footage. I've never found deploying gear/flap distracting. I use them both inside and outside of the circuit at a variety of points/times for a variety of reasons. I appreciate you taking the time to critique, but I think you've overblown your concerns. You may have a point about point 2 and if you find a reference for this anywhere, please do send it over.
@@TheFlyingReporter Then I'm guessing none of them have passed ATPL performance. My comments are meant with good intent as constructive criticism and none of the points are 'overplayed'. All are valid airmanship issues. In fact there's a lot more I could expand on. One of the main attributes needed of professional pilots is to accept constant review and appraisal throughout their careers. To be the best you can in GA one should embrace the same policy. Keep up the good work, but please. Do check that what you're teaching is technically correct.
@@davidbarrington8202 Thanks. I fly privately - not as an ATPL. I do appreciate the feedback, but its important that I also have the opportunity to point out where I disagree and where I am confident about my airmanship and actions. However, very willing to learn more about use of those piper POH charts in NCO - Do let me know if you can point to a reference to the Piper POH charts, and interpolation below sea level- really keen to get to the bottom of that one as a learning point.
I don't want to get into a bun fight on social media. Sadly your Facebook page won't load so I have sent you my contact details via a message on your website. I'm more than happy to discuss matters with you personally.
Having just done my ATPL Perf exam I’m fairly certain for commercial operations class B (like the arrow here) must be able to land within 70% of the LDA, or in other words, the performance manual figure when divided by 0.7 (same as multiplying by 1.43) should be less than the LDA
"Not exactly accurate... it's difficult to see..." Those charts had their place in the 1960s when a desktop digital calculator was more expensive than an iPad is today. (Though anyone who was decent with a slide rule could do these sorts of calculations reasonably quickly and more accurately if they had formulas to work from.) For this useful looking app, I wonder if the devs simply reversed out the formulas that reasonably well represent the lines on the graphs? It would be ideal if Piper, Cessna and other manufacturers officially stated formulas for those performance charts so we could officially plug in numbers and get a more precise result (keeping in mind that an extremely precise performance number has its limitations in the real world given the many, many messy variables particularly our own skills as pilots!)
Even if Piper, Cessna etc have not published the formulae, surely someone must have reverse engineered those charts and created a reasonably accurate calculation. Has anyone ever seen such I thing? I might try doing it myself with a spreadsheet - it would be a lot handier to use and less subject to mistakes than those fiddly graphs.
You should have done an airfield tour, there's a few things of interest at Damyns. The Tiger Club is based there, and they also operate the Pipistrel Electro from there. The little cafe is nice too!
I did what amounts to a double major in both aviation and computer science. This was back in 2000, but I wrote my own flight calculation software for weight and balance and performance calculations. It was a ton of fun working through the maths to do all these calculations in the software such that I didn't have to fudge things on a graph.
Thanks for the video!
Thanks for this Jon, performance calculations are something I’ve been pondering about for a while.
This is another example of your professionalism and care for doing it 'right!' Well done. BTW I'm jealous of all those lovely grass airports (or should I say aerodromes? ;-) ) you seem to have at your disposal. I love getting my little Piper T-Hawk off the pavement now and then. It takes me back, I guess. Cheers and thanks again for posting.
Great vid, Jon. Very useful info as always, thank you! 👌🏻👍🏻
A very good performance video that brings out the issues with paper performance charts, I have long thought an iPad app was needed for GA after using the Boeing Laptop tool for performance calculation on larger aircraft. What does concern me a little is the assumption that the aircraft will meet the flight manual numbers, back in the days before EASA the U.K. CAA required a flight test with an approved pilot to be done at each CofA renewal ( roughly similar to todays ARC ) . This flight test required quite a detailed investigation of the aircraft performance , quite a number of aircraft failed to meet the FM numbers and if the problem could not be rectified a performance write down was put in the aircraft flight manual. Add to this the fact told to me by a very well respected engine overhaul shop owner ( sadly long gone ) who for interest put a 200 HP engine that had reached TBO on his engine test bed, the engine made just over 180HP at full throttle. This all goes to show that the Factors that the CAA recommend are added to the FM performance calculation should IMO considered MANDATORY.
Another great video. Maybe one on the Gear Override could be interesting, how you use it how it works . Cheers
Excellent vid as always. Many thanks.
Nice one Jon. The Gyronimo app looks great. Looking forward to flying together in the Skyleader 400.
Brilliant - and useful reminder for all!
Thanks for the recap I’ve got my Cpl skills test coming up in a few weeks 😂😂
remember the rules about how much head/tailwind you can take - those factors came up with my examiner during the brief (and I dont think you can do the ground roll only for comm ops)
@@evanscm3 do you mean crosswind component or factors??
@@Matt67543 "not more than 50% of the headwind component and not less than 150% of the tailwind component of the reported wind be assumed...~"
My Musketeer's POH has tables for takeoff and landings. The best I can say for their accuracy is that they have the right number of digits.
That's not much help!
Thanks Jon. Had a look at that app and quite like it. Needs to be available for iPhone too.
Most performance charts are designed for MTOW configuration. If you’re flying by yourself, you are likely to be under.
Why would you change tank on approach especially over QE bridge. Change where you could land if tank was empty or something else went wrong
It's a POH/AFM checklist item. You switch to your fullest tank for approach. "APPROACH AND LANDING: Check to insure the fuel selector is on the proper (fullest) tank." I follow the POH.
That Gyronimo app looks handy - I checked it out but sadly our aircraft is not covered. That’s what you get for flying a classic PA24 Comanche ! 😊
Well, you will fly something different.. You could email them and ask?
@@TheFlyingReporter yup emailed yesterday and they would like me to send them the flight manual in pdf format, so fingers crossed they’ll add our old banger to the list!
Firstly. Whilst I congratulate John on producing his videos with good intent I would be much happier if he ensured that his productions were first over seen by a qualified flying instructor before publishing. The number of airmanship issues and questionable points that each one raises worries me that less experienced pilots might feel that his videos are AOPA approved as best recommended practice.
On this I one I note the following:
1. John is right to say that the only graphs applicable for an aircraft are those in your particular POH or user manual. However, in the case of several aircraft there are supplementary sections supplied by the CAA at the time of certification that make the performance chapter supplied by the manufacturer invalid. In the case of the Archer the FAA manual (and graphs) are in VB790. However the CAA published supplementary take off and landing graphs in VB737 which override the Piper ones. John should have been using those if his Arrow has a similar CAA supplement.
2. I stand to be corrected but if a performance graph only shows ISA beginning at sea level then extrapolation below that is not allowed. Using -300’ is not an approved way to use the graph.
3. Whilst John adds the CAA factor for grass and a ‘fudge factor’ for take-off to 50’ he ignores both on the subsequent discussions regarding landing roll. If that landing had been on wet grass the result might well not have turned out so well. Note the advertised tablet app also only deals with hard paved surfaces.
4. John mentions slope but then ignores it in all calculations. To be fair, unlike higher performance aircraft slope is not easily available for GA pilots. However, the CAA recommend applying a factor of 10% for every two per cent of gradient (Skyway Code page 51). So how can you calculate slope when it’s not published?
One method is to utilise Google Earth Pro and run a cursor from one end of the proposed runway to the opposite end. Reading the elevation shown on the lower right side of the map, the difference between each end can be noted. Dividing the elevation difference by the length and multiplying by 100 will show the runways overall slope in percentage which can then be used to apply a safety factor. This is particularly useful for farm strips and unlicenced fields.
From the airmanship aspect I also would urge people not to change tanks at low level and near the circuit. Any interruption in fuel flow will occur at the worst possible time and be a major distraction.
Also, the use of one stage of flap before or upon entering a circuit is unnecessary on a light aircraft. Along with the early use of gear both introduce speed limitations and distractions that result in reduced lookout and concentration. Gear on the downwind leg and taking the flaps on base is fine for any PA28.
Otherwise I thank John for taking the time to make his productions.
HI David. Thanks for the comments. I do think you might be overplaying this.
If it's any reassurance to you, the video was shared with a Flight Instructor prior to publication - they watched it three times and didn't find any fault.
It was then shared with my supporter community, which includes examiners and instructors. No comment was made.
For the avoidance of doubt, the videos aren't AOPA approved - AOPA is an advertiser.
On your numbered points...
1. The charts I use are the ones in my POH. I don't have a supplement, especially not any for the Archer, as I fly an arrow. The charts in my POH are identical to those in the app. I gave a caveat about use of the app.
2. Your second point is noted, and you may be correct. If you have a reference for this, please do send it over, because I've not found chapter and verse on this from a manufacturer/regulatory point of view. There is nothing in my POH as far as I can tell, that says I can interpolate 300 feet above SL, but not 300 feet below it.
3. I didn't discuss wet grass, snow, long grass, soft field etc, because none was applicable that day.
4. The slope was factored into my take off run as it's applicable but the detailed take off performance calculations were not shown/demonstrated in the video. The calculations demonstrated and detailed in the video related to the landing, which had an upslope. There is no CAA factor for an upslope, and so none was factored in. Any upslope would help a landing, not hinder it.
5. The fuel was switched at A1700, over the QE2 bridge, four miles from the airfield. I do not judge this to be unsafe - certainly not anymore unsafe than A1700 10 miles from the airfield.
6. I'm happy with the timing of my gear/flap selection. Flap was selected on base - editing may have condensed this sequence - I just checked the raw footage.
I've never found deploying gear/flap distracting. I use them both inside and outside of the circuit at a variety of points/times for a variety of reasons.
I appreciate you taking the time to critique, but I think you've overblown your concerns. You may have a point about point 2 and if you find a reference for this anywhere, please do send it over.
@@TheFlyingReporter Then I'm guessing none of them have passed ATPL performance. My comments are meant with good intent as constructive criticism and none of the points are 'overplayed'. All are valid airmanship issues. In fact there's a lot more I could expand on.
One of the main attributes needed of professional pilots is to accept constant review and appraisal throughout their careers. To be the best you can in GA one should embrace the same policy.
Keep up the good work, but please. Do check that what you're teaching is technically correct.
@@davidbarrington8202 Thanks. I fly privately - not as an ATPL. I do appreciate the feedback, but its important that I also have the opportunity to point out where I disagree and where I am confident about my airmanship and actions. However, very willing to learn more about use of those piper POH charts in NCO - Do let me know if you can point to a reference to the Piper POH charts, and interpolation below sea level- really keen to get to the bottom of that one as a learning point.
I don't want to get into a bun fight on social media. Sadly your Facebook page won't load so I have sent you my contact details via a message on your website.
I'm more than happy to discuss matters with you personally.
Excellent video except one par made me laugh. To convert 1,400 feet into meters divide by 3.28. That's it.
Air carrier regs require an additional 40% for landing distance over that required per flight manual calculations.
And private fliers in the UK add x 1.43 for landing.
Having just done my ATPL Perf exam I’m fairly certain for commercial operations class B (like the arrow here) must be able to land within 70% of the LDA, or in other words, the performance manual figure when divided by 0.7 (same as multiplying by 1.43) should be less than the LDA
@@henryyandell3222 Why would Jon be classified as commercial??? In the USA, no percentage adjustment is required for GA landing distances.
@@douglasb5046didn’t your initial comment mention commercial regs?
"Not exactly accurate... it's difficult to see..." Those charts had their place in the 1960s when a desktop digital calculator was more expensive than an iPad is today. (Though anyone who was decent with a slide rule could do these sorts of calculations reasonably quickly and more accurately if they had formulas to work from.) For this useful looking app, I wonder if the devs simply reversed out the formulas that reasonably well represent the lines on the graphs? It would be ideal if Piper, Cessna and other manufacturers officially stated formulas for those performance charts so we could officially plug in numbers and get a more precise result (keeping in mind that an extremely precise performance number has its limitations in the real world given the many, many messy variables particularly our own skills as pilots!)
Even if Piper, Cessna etc have not published the formulae, surely someone must have reverse engineered those charts and created a reasonably accurate calculation. Has anyone ever seen such I thing? I might try doing it myself with a spreadsheet - it would be a lot handier to use and less subject to mistakes than those fiddly graphs.
Hi not a question about this video but how do you get your gear up so early my arrow it will not go up till I get the 100mph
I override the auto gear extension system for take off.
@@TheFlyingReporter makes sense. I was thinking wow that gear come up quick. do you put that back on just before landing checks.
@antonyrawson9231 I put it on as part of my after take off checks.
@@TheFlyingReporter cool thanks love the videos