Flaps on takeoff or not?
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How does your flap setting affect the taxiing pitch authority, which I presume is only really a function of the elevator deflection and the speed?
I strongly feel that new pilots should not be exploring techinquies which are presented as prohibited or could be interpreted as not approved or to be avoided. These pilots, however, should be at least familiar with some uncommon, but conforming operations, where these can be safely and consistantly demonstrated, particularly when they ask. It is up to the instructor first hand, and the flying community in general, to mentor new pilots with experienced based wisdom. Some of this wisdom should include optimizing the performance of the aircraft in certain situations, and pointing out to the new pilot that techinques which fall within the scope of approved etc in a flight manual, should also fall within their skill set.
Every takeoff and landing which I do, which has no other factors determining which techinque would be most appropriate, will be either short or soft technique. "Regular" takeoffs and landings seem to me to require the least precision. To me, it is simply a lost opportunity, to takeoff or land, without practicing a technique appropriate for the aircraft and conditions.
I see aircraft taxiing around with control positions indicating that the pilot is apparently unaware that they are controlling an aircraft which is moving throught the air. The fact that it is on the ground is probably what is creating this relaxed attitude, but it is still moving through the air! Why not practice flying it before you have to leave the ground, and imediately when you return? The plane is flying, why is the pilot not? Pilot lands plane, three wheels contact the ground, and pilot promply lets go, and gives up flying. Does the pilot not realize how much braking effort can be saved by holding the crontrols back through the roll out?
I see aircraft hurtling down the runway with no takeoff flap set, and no nose up control held. That aircraft will be going 10 or so? MPH faster when it leaves the ground. Additional maintenance cost ( risk of shimmy and all those other undesirable landing gear things), yet that pilot will whine about the cost of flying. If all the pilots were paying dierectly for the specific wear and tear they cause to the aircraft they fly, they'd care more. Some instructors fall within this accusation - but no slight intended to anyone in particular.
As has been mentioned earlier, the flight manual for the aircraft, is based on the manuafacturer's testing with a new condtion aircraft. It was not an aircraft which was "experienced" and maybe a little loose, thus needing a more gentle touch. When a system on the aircraft (flaps, for example) is available, to reduce wear and tear on the landing gear, it should be safely and compliantly used, not ignored. New pilots should know this.
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I see aircraft hurtling down the runway with no takeoff flap set, and no nose up control held. That aircraft will be going 10 or so? MPH faster when it leaves the ground. Additional maintenance cost ( risk of shimmy and all those other undesirable landing gear things), yet that pilot will whine about the cost of flying.
Two stages and I'm able to avoid that bumb in the middle of the runway when I'm at high speed.
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Just out of interest, what rate of climb did you get after that 40 flap takeoff?
Re full flap takeoff and the C150.
When I did my PPL near Montreal we were practicing PFL's in the C150 one very hot muggy summer day with myself, my 180 lb instructor, and nearly full tanks. The last when went pretty well and at 300 ft AGL with 40 deg flaps out I was told to go around. Full power and flaps up......only the flaps did not move. At full power the aircraft would just maintain level flight and would not climb. We flew the 10 miles back at 300 ft and landed. This was 33 yrs ago but it is still a rather vivid memory and after that I am carefull with large flap settings and low powered Cessna's.....
As a young Instructor/charter pilot I once used 40 deg of flap in a C 172 to get it to lift off from a very muddy field. The aircraft would not accelerate above 45 kts so a sudden application of 40 deg flap caused the aircraft to balloon up enough to break free and then some carefull stick jockeying kept it in the air as I slowly accelerated to a sensible speed. When I returned the CFI/Chief Pilot asked why the aircraft was covered in mud. When I explained he said "Good Flying, Now WTF were you doing going into the field in that first place"
That being said the use of large amounts of flap on takeoff is common with float plane takeoffs. The C180/185 manual flap systemis is particualy usefull as you can finesse that little bit extra bit of flap between the 20 and 30 deg notches to help the aircraft break free of the water when it is heavily loaded and/or the wind is calm
When I did my PPL near Montreal we were practicing PFL's in the C150 one very hot muggy summer day with myself, my 180 lb instructor, and nearly full tanks. The last when went pretty well and at 300 ft AGL with 40 deg flaps out I was told to go around. Full power and flaps up......only the flaps did not move. At full power the aircraft would just maintain level flight and would not climb. We flew the 10 miles back at 300 ft and landed. This was 33 yrs ago but it is still a rather vivid memory and after that I am carefull with large flap settings and low powered Cessna's.....
As a young Instructor/charter pilot I once used 40 deg of flap in a C 172 to get it to lift off from a very muddy field. The aircraft would not accelerate above 45 kts so a sudden application of 40 deg flap caused the aircraft to balloon up enough to break free and then some carefull stick jockeying kept it in the air as I slowly accelerated to a sensible speed. When I returned the CFI/Chief Pilot asked why the aircraft was covered in mud. When I explained he said "Good Flying, Now WTF were you doing going into the field in that first place"
That being said the use of large amounts of flap on takeoff is common with float plane takeoffs. The C180/185 manual flap systemis is particualy usefull as you can finesse that little bit extra bit of flap between the 20 and 30 deg notches to help the aircraft break free of the water when it is heavily loaded and/or the wind is calm
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There's a couple different schools of thought to flaps on takeoff when flying soft/short field. If the 206 I was going to fly had 5 pax and bags in the back... the tail sits maybe 7 inches off the ground... so no need to pull all the way back on that control wheel to keep the nose light and protected on the rough runway. Normally I would have flap 10 set before the roll.... flaps 20 would come in handy when you had a impala or goat or whatever jump out on the runway last second... no time left to stop but enough speed to get into ground effect...drop the 20 and up you. Never would I start the takeoff roll with 20... that's just too much unnecessary drag on the roll... better to drop to 20 last second if you are about to balloon up to safety. Some pilot will opt to start the takeoff roll with 0 flap to get up to speed asap then drop to 10 or 20 for an early up well...
In the caravan, flaps 20 is standard for takeoff... dropping to 30 (full flap) last second helps to get up early too... just don't try and escape ground effect too soon! Starting a roll with full flaps 30 is approved if you have the APE stall kit... comes in handy if the nose wheel's going to take a beating on the runway since full flap will get that nose up into a wheelie right away with the control wheel full back. Then just wheelie it out until the plane is ready to get airborne. Just need to make sure your nose wheel is barely off the ground... otherwise the flaps are introducing way too much drag and killing your effort to make a short takeoff roll.
Of course a flap motor failure / asymmetric flaps could always happen so be ready for the consequences. Playing with flaps on takeoff in the bush certainly has its merits. However, using flaps 30 for takeoff is not a good idea in a short caravan... in an engine failure you'll lose the effectiveness of your elevator, and depending on CofG, unable to pitch down for a stall recovery. Also it's not approved.
I am curious though, how do you float guys typically use your flaps for takeoff? Looking for some insight from the float world!
In the caravan, flaps 20 is standard for takeoff... dropping to 30 (full flap) last second helps to get up early too... just don't try and escape ground effect too soon! Starting a roll with full flaps 30 is approved if you have the APE stall kit... comes in handy if the nose wheel's going to take a beating on the runway since full flap will get that nose up into a wheelie right away with the control wheel full back. Then just wheelie it out until the plane is ready to get airborne. Just need to make sure your nose wheel is barely off the ground... otherwise the flaps are introducing way too much drag and killing your effort to make a short takeoff roll.
Of course a flap motor failure / asymmetric flaps could always happen so be ready for the consequences. Playing with flaps on takeoff in the bush certainly has its merits. However, using flaps 30 for takeoff is not a good idea in a short caravan... in an engine failure you'll lose the effectiveness of your elevator, and depending on CofG, unable to pitch down for a stall recovery. Also it's not approved.
I am curious though, how do you float guys typically use your flaps for takeoff? Looking for some insight from the float world!
What is a " stage " of flap you people speak of?
Is it something like " finals " ?
Is it something like " finals " ?
Like the DR400 which has first notch 15 degrees second 60 degrees
As in pull the handle a bit and let go that's takeoff. Pull more and let go that's landing flap.
Or just forget it as they don't actually have much effect anyway. (on a wooden Robin, anyway......) flying off 720 metres of mud, still......got really wet again washing it off yesterday. I suspect the runway will soon all be just in front of the hangar, next to the taps.
Folk do seem to get all het up here, don't they?
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Good, experienced, real-world info from BPF on the use of flaps not outlined in the POH.
For the OP, I always use F10 for takeoff when flying the 172 with old 145 horse or newer 150 HP engine. Generally speaking, max lift/min drag combo with flaps occurs when flaps are set to the same angle as an aileron in max down deflection, which is pretty close to F10. This results in less runway used and prolongs tire life to a degree (and is much more comfortable with a rental aircraft that has an out of balance tire(s) with the attendant vibration after liftoff). Raise the nose a bit at the recommended speed and let it fly off when its ready. You can then milk the flaps up slowly after liftoff to improve climb performance when you have good speed. If heavy and with a turn required right after takeoff, F10 will also provide a bit more stall margin while in a bank. It will also feel better if the CG is close to the aft portion of the envelope when you have make that slow turn.
Wish my son's 170B with O-300 had a F10 position. We use the F20 notch at sea level and milk them up after liftoff. At higher DA's on a hot day, that (F20 initially) doesn't necessarily work. One has to adapt...but then, that's flying.
The 185 specifies Flaps 0-20 for takeoff. I use F20 and raise them to F10 right after liftoff for an increased climb rate, then up when clear of any obstacles. The 300 HP allows the drag of more flaps and the tail comes up a bit quicker (by itself), which reduces drag and takeoff distance. A buddy uses F10 on his 185, but I think his wing washout is set differently than mine...but that's another topic. He also doesn't have WingX STOL, which might be part of the reason, although I used F20 before installing the kit.
Hope this background info helps with your decision.
For the OP, I always use F10 for takeoff when flying the 172 with old 145 horse or newer 150 HP engine. Generally speaking, max lift/min drag combo with flaps occurs when flaps are set to the same angle as an aileron in max down deflection, which is pretty close to F10. This results in less runway used and prolongs tire life to a degree (and is much more comfortable with a rental aircraft that has an out of balance tire(s) with the attendant vibration after liftoff). Raise the nose a bit at the recommended speed and let it fly off when its ready. You can then milk the flaps up slowly after liftoff to improve climb performance when you have good speed. If heavy and with a turn required right after takeoff, F10 will also provide a bit more stall margin while in a bank. It will also feel better if the CG is close to the aft portion of the envelope when you have make that slow turn.
Wish my son's 170B with O-300 had a F10 position. We use the F20 notch at sea level and milk them up after liftoff. At higher DA's on a hot day, that (F20 initially) doesn't necessarily work. One has to adapt...but then, that's flying.
The 185 specifies Flaps 0-20 for takeoff. I use F20 and raise them to F10 right after liftoff for an increased climb rate, then up when clear of any obstacles. The 300 HP allows the drag of more flaps and the tail comes up a bit quicker (by itself), which reduces drag and takeoff distance. A buddy uses F10 on his 185, but I think his wing washout is set differently than mine...but that's another topic. He also doesn't have WingX STOL, which might be part of the reason, although I used F20 before installing the kit.
Hope this background info helps with your decision.
