Safest go-around procedure
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Safest go-around procedure
I just had a fairly close call on a go-around in a Grumman Cheetah during a full-flap landing on a 3000' runway with some trees, houses, and power lines just past the far end. I came in high and fast, floated, and applied full power for a go-around. The plane took forever to accelerate from 50 to 65 KIAS in ground effect, and when it finally did, the climb rate was minimal, and I barely cleared the obstacles. By the time I had any positive rate of climb to speak of, I didn't want to touch the flaps for the fear of sinking right into the obstacles. However, the Cheetah POH recommends the following go-around procedure:
"Should a landing be balked, apply full power immediately; carburetor heat OFF; establish a positive rate of climb at 60-65 KIAS (69-75 MPH); retract the flaps and trim for normal climb."
So my question is, is there anything I could've done better? My suspicion is that I should have ignored the procedure recommended in the POH and retracted a notch of flaps immediately after application of full power, without waiting for positive rate of climb. Thoughts?
"Should a landing be balked, apply full power immediately; carburetor heat OFF; establish a positive rate of climb at 60-65 KIAS (69-75 MPH); retract the flaps and trim for normal climb."
So my question is, is there anything I could've done better? My suspicion is that I should have ignored the procedure recommended in the POH and retracted a notch of flaps immediately after application of full power, without waiting for positive rate of climb. Thoughts?
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What was the max landing weight of the aircraft and what was your actual landing weight.
What did the landing performance calculation suggest ?
Was there a tailwind present?
Rgds
What did the landing performance calculation suggest ?
Was there a tailwind present?
Rgds
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Did you reduce the flap from full to take off after applying full power? On applying full power you should reduce flap to the take off setting then wait for the speed, and climb, before retracting the flaps altogether.
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> What was the max landing weight of the aircraft and what was your
> actual landing weight.
Max landing weight: 2200 lbs.
Actual landing weight: 2110 lbs.
> What did the landing performance calculation suggest ?
Wouldn't a take-off performance calculation be more appropriate for go-arounds? The POH only has take-off performance charts for the recommended flap setting (no flaps) so it doesn't directly apply here.
Anyway, the landing performance table shows that there was plenty of room for me to safely land; I only needed ~1000' of the 3000' runway, but as I said before, I came in too high and fast, and decided to go around.
> Was there a tailwind present?
It was pretty much a direct cross-wind landing: cross-wind component was about 11 knots, and tailwind component was only about 1-2 knots.
> Did you reduce the flap from full to take off after applying full power?
No, I did not, because the POH recommended waiting for positive rate of climb before messing with the flaps.
> On applying full power you should reduce flap to the take off setting
> then wait for the speed, and climb, before retracting the flaps
> altogether.
The recommended take-off setting is no flaps, so I don't think that would work too well. However, I think that going from 30 to 20 deg of flaps immediately after application of full power may have been the thing to do. Are there any safely issues with doing this while still in ground effect, such as the plane dropping the nose and crashing into the runway?
> actual landing weight.
Max landing weight: 2200 lbs.
Actual landing weight: 2110 lbs.
> What did the landing performance calculation suggest ?
Wouldn't a take-off performance calculation be more appropriate for go-arounds? The POH only has take-off performance charts for the recommended flap setting (no flaps) so it doesn't directly apply here.
Anyway, the landing performance table shows that there was plenty of room for me to safely land; I only needed ~1000' of the 3000' runway, but as I said before, I came in too high and fast, and decided to go around.
> Was there a tailwind present?
It was pretty much a direct cross-wind landing: cross-wind component was about 11 knots, and tailwind component was only about 1-2 knots.
> Did you reduce the flap from full to take off after applying full power?
No, I did not, because the POH recommended waiting for positive rate of climb before messing with the flaps.
> On applying full power you should reduce flap to the take off setting
> then wait for the speed, and climb, before retracting the flaps
> altogether.
The recommended take-off setting is no flaps, so I don't think that would work too well. However, I think that going from 30 to 20 deg of flaps immediately after application of full power may have been the thing to do. Are there any safely issues with doing this while still in ground effect, such as the plane dropping the nose and crashing into the runway?
All of the Grumman series have a simple flap (ie no slot or fowler action). All they do is generate drag so they should be fully retracted after full power is applied and the airplane has started climbing.
Also the Grumman series demand accurate flying to achieve the desired climb performance. Vx for the Cheetah is 68 kts and a speed even a few knots slow will have a marked impact on performance.
Not saying this was the case for you, but I have noticed a lot of pilots, when conducting a near the runway low speed go around, allow the nose to pitch up as the power is applied. This causes the aircraft to climb out of ground effect while still at a very low airspeed and results in an excessively long period where the aircraft is only very slowly accelerating to Vx. The tendency then is to hurry the climb at too low an airspeed which only makes things worse. You have to the discipline to hold the aircraft in a level attitude in ground effect (ie no more than 15 feet above the runway) until the airplane accelerates to it Vx before starting to climb.
Also the Grumman series demand accurate flying to achieve the desired climb performance. Vx for the Cheetah is 68 kts and a speed even a few knots slow will have a marked impact on performance.
Not saying this was the case for you, but I have noticed a lot of pilots, when conducting a near the runway low speed go around, allow the nose to pitch up as the power is applied. This causes the aircraft to climb out of ground effect while still at a very low airspeed and results in an excessively long period where the aircraft is only very slowly accelerating to Vx. The tendency then is to hurry the climb at too low an airspeed which only makes things worse. You have to the discipline to hold the aircraft in a level attitude in ground effect (ie no more than 15 feet above the runway) until the airplane accelerates to it Vx before starting to climb.
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I confess I know nothing about the AA5 series but am familiar with cessna singles. The landing flap setting gives lots of drag, while it would be daft going from full flap to nothing on applying power and commencing the go around it makes a lot of sense to reduce the flap to the intermediate setting to reduce the drag therefore increasing your acceleration. The 172 that I fly has a landing flap setting of 30 degrees and recommended take off of zero flap unless operating from a soft/short field. In the case of a go around after applying full flap in the cessna I would reduce to 20 degrees immediately then 10 degrees as the speed is increasing and then zero once a climb is established and the speed is safe.
Unless you have lots of excess power then it is going to be very hard to accelerate (an climb) without getting rid of the drag flap settings.
Unless you have lots of excess power then it is going to be very hard to accelerate (an climb) without getting rid of the drag flap settings.
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Big Pistons, I often enjoy your posts and agree with you. On this occasion I don't, because you generalise too much.
The procedures in the Grumman POH have undergone some kind of scrutiny (I wouldn't like to say how much, but they passed the FAA's tests) and they are the published procedures for the aircraft. They are the procedures by which, by law, the aircraft must be flown, and they are the procedures which, if followed, achieve the relevant safety standards.
The OP says he came in high and fast, yet he left the go-around until the last minute, it seems. That's a learning point for him. He handled the aircraft through the event without accident and probably learned about handling from that.
The AA5 is a wonderful training aircraft. Anyone can fly it, almost anyone can land it (they really made a mess of designing the nose landing gear), but a decent examiner or instructor can tell in the shortest time how skilled the student or candidate is. I loved instructing on them, and flying them myself, because flying them well requires skill.
The procedures in the Grumman POH have undergone some kind of scrutiny (I wouldn't like to say how much, but they passed the FAA's tests) and they are the published procedures for the aircraft. They are the procedures by which, by law, the aircraft must be flown, and they are the procedures which, if followed, achieve the relevant safety standards.
The OP says he came in high and fast, yet he left the go-around until the last minute, it seems. That's a learning point for him. He handled the aircraft through the event without accident and probably learned about handling from that.
The AA5 is a wonderful training aircraft. Anyone can fly it, almost anyone can land it (they really made a mess of designing the nose landing gear), but a decent examiner or instructor can tell in the shortest time how skilled the student or candidate is. I loved instructing on them, and flying them myself, because flying them well requires skill.
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Thank you for the comments, everyone. The recommended go-around procedure in the Grumman AA-5A POH (Full power immediately; carburetor heat OFF; establish a positive rate of climb at 60-65 KIAS; retract the flaps and trim for normal climb) still does not make sense to me, for the following reason: say I was operating at a higher density altitude than I was, and was unable to leave ground effect with full flaps down. If I were to follow the procedure verbatim, I would stay in ground effect until I crashed into the obstacles at the end of the runway.
It appears that most people here are in agreement that it's OK to retract at least one notch of flaps while still in ground effect. If anyone sees this as a serious safety issue, please speak up.
It appears that most people here are in agreement that it's OK to retract at least one notch of flaps while still in ground effect. If anyone sees this as a serious safety issue, please speak up.
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Yes, I do. I think you ended up in a situation beyond your training and which the aircraft was not tested for. Avoid that situation in future, and always remember, the moment you step aside from the proscribed procedures for any aircraft two things happen: first, you become exclusively responsible for the outcome and second, you enter uncharted, and possibly unexplored, territory at your peril.
If you fly the aircraft correctly, you shouldn't need to experiment.
Next time, fly the approach properly or go around early enough for it not to be an issue.
I agree that there are some interesting things about the AA5A at low speeds; in testing, erroneous airspeed calibration sometimes proved to be problematic, but it's no DC8, and nor does it need handling like one.
Final thought... Think about what would happen if you could try taking various AA5As to a safe altitude. Establish the 1g flap full stall speed iteratively, and then go to that speed plus 3 knots and retract some flap. The pitching moment and wing drop may be significant, and that's a good reason to achieve a safe margin above the stall speed for the configuration you're about to adopt before adopting it. I mention this even though in ground effect it will be different, but testing in ground effect is difficult and hazardous, and therefore usually done in tunnels or by modelling.
If you fly the aircraft correctly, you shouldn't need to experiment.
Next time, fly the approach properly or go around early enough for it not to be an issue.
I agree that there are some interesting things about the AA5A at low speeds; in testing, erroneous airspeed calibration sometimes proved to be problematic, but it's no DC8, and nor does it need handling like one.
Final thought... Think about what would happen if you could try taking various AA5As to a safe altitude. Establish the 1g flap full stall speed iteratively, and then go to that speed plus 3 knots and retract some flap. The pitching moment and wing drop may be significant, and that's a good reason to achieve a safe margin above the stall speed for the configuration you're about to adopt before adopting it. I mention this even though in ground effect it will be different, but testing in ground effect is difficult and hazardous, and therefore usually done in tunnels or by modelling.
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Kerling-Approsh KG: While I appreciate your feedback, I think that whether I should have gone around sooner is a totally separate issue from the one I'm trying to address here. (Short answer, which I knew myself before I posted here: yes, I should have.) Still, there are obviously many other go-around scenarios that involve application of full power a few feet above the runway. Your take on it is to always follow the POH to the letter and wait until positive rate of climb before retracting flaps. I accept your position, but I have encountered enough situations where the POH procedures were not optimal, so I'd like to solicit more feedback from pilots who are familiar with the Cheetah, and see what their take on it is.
Drag flap
I confess to no knowledge of AA5; However my approach is a simple one effective for all types;
(NOTE - I.M.H.O in panic sitations anything complicated or too detailed just doesn't work but I am a basic type Human MK 1 & not PERFECT BY ANY STRETCH OF THE IMAGINATION)
Here tis'
1) Apply full power IMMEDIATELY
2) Retract drag flap IMMEDIATELY - BUT NOT LIFT FLAP
3) Pray for effective R.O.C
4) Thank god for power of prayer ref' Item 3 !
5) In the event of items 1,2 & 3 non-effectivness tighten belts & brace for impact !
Take care folks - tis' better to be a pilot of extreme skills & knowledge & even better to not be in a situation requiring use of such extreme skills & knowledge in the first place - if at all possible.
(NOTE - I.M.H.O in panic sitations anything complicated or too detailed just doesn't work but I am a basic type Human MK 1 & not PERFECT BY ANY STRETCH OF THE IMAGINATION)
Here tis'
1) Apply full power IMMEDIATELY
2) Retract drag flap IMMEDIATELY - BUT NOT LIFT FLAP
3) Pray for effective R.O.C
4) Thank god for power of prayer ref' Item 3 !
5) In the event of items 1,2 & 3 non-effectivness tighten belts & brace for impact !
Take care folks - tis' better to be a pilot of extreme skills & knowledge & even better to not be in a situation requiring use of such extreme skills & knowledge in the first place - if at all possible.
Last edited by old-timer; 30th Jan 2011 at 20:41. Reason: typo
I confess I know nothing about the AA5 series but am familiar with cessna singles. The landing flap setting gives lots of drag, while it would be daft going from full flap to nothing on applying power and commencing the go around it makes a lot of sense to reduce the flap to the intermediate setting to reduce the drag therefore increasing your acceleration. The 172 that I fly has a landing flap setting of 30 degrees and recommended take off of zero flap unless operating from a soft/short field. In the case of a go around after applying full flap in the cessna I would reduce to 20 degrees immediately then 10 degrees as the speed is increasing and then zero once a climb is established and the speed is safe.
Unless you have lots of excess power then it is going to be very hard to accelerate (an climb) without getting rid of the drag flap settings.
Unless you have lots of excess power then it is going to be very hard to accelerate (an climb) without getting rid of the drag flap settings.
Last edited by Big Pistons Forever; 30th Jan 2011 at 21:12.
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Darien, aircraft are certified to fly within an envelope. For example, the elevator on a twin-jet with underslung engines is the size it is, to cope with a full thrust go-around at Vref-5 knots. Slower than that, and there is no guarantee of the aircraft being controllable (read the report on the Turkish B737 crash at Schiphol if you need to see a practical outcome of this). Similarly, your AA5A is certified within limits, and your job as the pilot is to stay within those limits. Within those limits, the procedures in the POH should be good. Outside those limits, they may not be, and that's where your problems began. Hence why it's so important to stay within the envelope.
You mention that you've encountered several situations in which the POH procedures were not optimal... If true, you should consider finding some high quality training or re-training. That shouldn't be happening (the number of times it's happened to me in several thousand hours of flying, training, testing pilots and testing aircraft is very small).
Old-timer, would you be so kind as to describe how one might define 'drag flap' and 'lift flap' on a particular aircraft, please? None of the training I've received, nor the text books I have on design, certification, testing, or aerodynamics are any help.
You mention that you've encountered several situations in which the POH procedures were not optimal... If true, you should consider finding some high quality training or re-training. That shouldn't be happening (the number of times it's happened to me in several thousand hours of flying, training, testing pilots and testing aircraft is very small).
Old-timer, would you be so kind as to describe how one might define 'drag flap' and 'lift flap' on a particular aircraft, please? None of the training I've received, nor the text books I have on design, certification, testing, or aerodynamics are any help.
Thank you for the comments, everyone. The recommended go-around procedure in the Grumman AA-5A POH (Full power immediately; carburetor heat OFF; establish a positive rate of climb at 60-65 KIAS; retract the flaps and trim for normal climb) still does not make sense to me, for the following reason: say I was operating at a higher density altitude than I was, and was unable to leave ground effect with full flaps down. If I were to follow the procedure verbatim, I would stay in ground effect until I crashed into the obstacles at the end of the runway.
It appears that most people here are in agreement that it's OK to retract at least one notch of flaps while still in ground effect. If anyone sees this as a serious safety issue, please speak up.
It appears that most people here are in agreement that it's OK to retract at least one notch of flaps while still in ground effect. If anyone sees this as a serious safety issue, please speak up.
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Big Pistons, I enjoyed your last post there. Only clarification would be, which Vx? If I bought an aircraft, or flew it regularly and had time to kill one day, I would go and test it and establish the correct values of Vs etc and then all the others that follow, including the climb speeds, but I think it would be better for our original poster to use the POH figures, which should be conservative at <MTOW or MLW.
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Right, Vx is lower with full flaps; Cheetah POH recommends 60-65 KIAS.
In terms of the POH procedures not always being optimal, here's an example pertaining to flaps on the Cheetah: the POH recommends no-flap takeoffs, but I was told by several Cheetah owners to take off with 10 degrees of flaps for best ROC, and have verified this myself. More generally, I guess I was trained to treat the POH as a recommendation rather than a Bible, and speak to the actual people who fly that particular airplane a lot to find out what works best.
In terms of the POH procedures not always being optimal, here's an example pertaining to flaps on the Cheetah: the POH recommends no-flap takeoffs, but I was told by several Cheetah owners to take off with 10 degrees of flaps for best ROC, and have verified this myself. More generally, I guess I was trained to treat the POH as a recommendation rather than a Bible, and speak to the actual people who fly that particular airplane a lot to find out what works best.
Right, Vx is lower with full flaps; Cheetah POH recommends 60-65 KIAS.
In terms of the POH procedures not always being optimal, here's an example pertaining to flaps on the Cheetah: the POH recommends no-flap takeoffs, but I was told by several Cheetah owners to take off with 10 degrees of flaps for best ROC, and have verified this myself. More generally, I guess I was trained to treat the POH as a recommendation rather than a Bible, and speak to the actual people who fly that particular airplane a lot to find out what works best.
In terms of the POH procedures not always being optimal, here's an example pertaining to flaps on the Cheetah: the POH recommends no-flap takeoffs, but I was told by several Cheetah owners to take off with 10 degrees of flaps for best ROC, and have verified this myself. More generally, I guess I was trained to treat the POH as a recommendation rather than a Bible, and speak to the actual people who fly that particular airplane a lot to find out what works best.
You say you have "verified" that the airplane has a better ROC with 10 deg flaps. So that means you used a calibrated test instrumentation set up and flew enough takeoff profiles to generate sufficient test data that it could be extrapolated to all air density conditions ?
I am guessing you have decided you "feel" the aircraft climbs better on the basis of the power of suggestion of an airport urban myth.
It's simple, when in doubt follow the POH
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All I can say is that with 10 degrees of flaps, ROC as measured by VSI is about 100 fpm better in my typical flight environments. Aviation Consumer, as well as the AA-5 owners I've spoken to, say the following:
"Takeoff and climb performance can be enhanced by ignoring book procedures, which call for flaps up. Some experienced Tiger/Cheetah pilots put down about one-third flaps when takeoff performance is critical."
http://www.randyarmadillo.com/flying...nsumer_1_1.pdf
"Takeoff and climb performance can be enhanced by ignoring book procedures, which call for flaps up. Some experienced Tiger/Cheetah pilots put down about one-third flaps when takeoff performance is critical."
http://www.randyarmadillo.com/flying...nsumer_1_1.pdf
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POH or not to POH
In terms of the POH procedures not always being optimal, here's an example pertaining to flaps on the Cheetah: the POH recommends no-flap takeoffs, but I was told by several Cheetah owners to take off with 10 degrees of flaps for best ROC, and have verified this myself. More generally, I guess I was trained to treat the POH as a recommendation rather than a Bible, and speak to the actual people who fly that particular airplane a lot to find out what works best.
As mentioned in another post - the POH was developed by the (actual) people who created and tested the aircraft, and one should assume they know more about the aircraft than most owners combined. As for the use of flaps, or no flaps, I'm sure every imaginable scenario was test flown and graphed before the aircraft was certified.
I admire pilots like darien-I who after having had a problem reach out to learn more about what he/she could have done different. Those are qualities that makes a pilot better.
However, as none of us were there with you and we don't really know how you fly I would advice you find an instructor - preferably one that believes in POHs and knows the Cheetah - and go do some practise circuits with go-arounds. Or go practise some yourself, either from a safe altitude away from the airport, in the ciruit but from a higher go-around height, or at a runway with adequate remaining runway lenght so you don't hurt yourself in the process should you not achieve a good ROC.
Your reason for the close call can be many and doesn't necessary relate directly to any procedure in the POH. Even following a POH procedure can get you hurt if it's not done in a timely and accurat manner.
All I can say is that with 10 degrees of flaps, ROC as measured by VSI is about 100 fpm better in my typical flight environments. Aviation Consumer, as well as the AA-5 owners I've spoken to, say the following:
"Takeoff and climb performance can be enhanced by ignoring book procedures, which call for flaps up. Some experienced Tiger/Cheetah pilots put down about one-third flaps when takeoff performance is critical."
http://www.randyarmadillo.com/flying...nsumer_1_1.pdf
"Takeoff and climb performance can be enhanced by ignoring book procedures, which call for flaps up. Some experienced Tiger/Cheetah pilots put down about one-third flaps when takeoff performance is critical."
http://www.randyarmadillo.com/flying...nsumer_1_1.pdf