PA-28 short field take off flap setting
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There is a well known tecnique though for short fields. Full power against brakes. No flap, release brakes for max acceleration, about 10 mph below normal lift off speed pull full flap.The plane will jump into the air,at which point you must not pull back! Allow the plane to accellerate whist slowly retracting flaps to first stage, effectively trading sink against accelleration and once speed is sufficient ,establish a posative climb.
First of all the PA28 is not exactly overpowered, especially the -140. By pulling full flap at 10 mph below lift off, you are putting yourself in a low-speed, high drag configuration, less aileron authority, and your ability to clear a 50 ft obstacle, or any other obstacle will be severely impaired as you will require longer in ground effect to accelerate out of it and start climbing. As I recall the manual allowed for 1-notch of flaps on takeoff in short-field situations. And yes, you can stall out the stabilator on a PA28. It's quite a suprise to be applying downforce to the stabilator (i.e. pulling back on the stick as in flare) and have the nose come down rather brutally.
There is a little thing called the "takeoff performance chart" in every POH. It has calculations made by test pilots and engineers. They have conducted tests that determine what configuration and technique will require the shortest takeoff distance to clear obstacles. If you deviate from the procedure you become a test pilot, and you will no longer meet the calculated takeoff distance requirement. Any deviation you use will be either less safe, or will require more distance than in the POH.
There is a proper way to execute a short-field takeoff in a PA28 or any other aircraft for that matter: know your gross weight, calculate your density altitude, note the type of runway surface and approximate height of obstacles at the departure end of the runway, have a good estimate of wind direction and strength, then sit down with the POH and determine your takeoff distance. If the distance available is shorter than what the book says you need, the only safe alternative is to offload weight until you can meet the book performance with a safe margin, or as you said earlier take it out on a lorry. A big problem with many aircraft (the C150 can get into this mess too) is that it is very easy to land in a field you can longer depart from. If you determine it can be safely done from the POH, then follow the POH's procedure to the letter, for short-field takeoffs if one is published.
In my younger and foolish days with my PA28 I did try to pull in my 1 notch of flaps near takeoff speed, at max. gross, to "leap" into the air as has often been suggested and it nearly killed me. First of all it lengthened our ground run as I was distracted from actually flying the aircraft, and that in turn, ensured that I only barely cleared the obstacles at the end of the 2500 ft runway. I was shocked to learn, after calculating density altitude after the fact, just how little margin of error I had (2200 ft required, 2500 ft available). I swear those treetops tickled my my ar$e on the way up. I never want to be in that situation again.
My current ride, a Beech Sundowner 180, has a 65 knot rotate speed and the manual does not call for flaps on a short-field departure and does not have a specific short field procedure. It has laminar wings with a high wing loading and also a stabilator. Earlier versions allowed 1-notch takeoffs but there were accidents as the plane had trouble flying out of ground effect. So later versions like mine had this removed from the POH. I tried, on a long, unobstructed runway various techniques for getting it off the ground at less than 65 knots.
None of them I considered safe. The safest practice is to land in a field that you have determined beforehand, you will be able get out of.
Fly smart, fly safe.
Beech
Last edited by BeechNut; 1st Apr 2009 at 16:14.
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You can learn so many useful things from Pprune.
I'm just about at 200 hours on my PPL, which according to several informed websites makes me "invincible"
. I also fly a Warrior.
I'll be trying out all these good ideas at the weekend on a 400m strip that I plan to fly to.
Thanks for the excellent advice.
I'm just about at 200 hours on my PPL, which according to several informed websites makes me "invincible"
. I also fly a Warrior.I'll be trying out all these good ideas at the weekend on a 400m strip that I plan to fly to.
Thanks for the excellent advice.
Moderator
In 30 plus years of flying, I havn't been bit yet either. Mostly luck, I'm certain. Early on (around 200 hours) I had the excuse of in experience to justify some of my foolish behaviour. Long ago, I lost that excuse - I now know better. I get to be inexperienced in helicopters now...
There are many things which I can still do very well in airplanes, a number of them not strictly in accordance with what the flight manual says. Some of these things I occasionally allude to here, many of them I never would. The fact that I am able to safely handle an aircraft during manuevering "outside the norm", does not mean that I'd write it into cyberspace! Odd flap techniques are know to me for water flying. I would happily demonstrate them, but will not describe them here. I don't want my conscience dealing with someone wrecking a plane because they tries something I wrote here, without the benefit of qualified, prepared supervision.
Changing flap settings during takeoff introduces simulaineous distraction, and change in flying qualities, neither of which are appropriate during a takeoff by a pilot who is new, or new to type.
New pilots are reminded that just because you read that people do things in planes, don't assume you can get away with it too! You start your flying career with a full bag of luck, and an empty bag of experience. The trick is to use your judgement to fill the experience bag, before you empty the bag of luck!
There are many things which I can still do very well in airplanes, a number of them not strictly in accordance with what the flight manual says. Some of these things I occasionally allude to here, many of them I never would. The fact that I am able to safely handle an aircraft during manuevering "outside the norm", does not mean that I'd write it into cyberspace! Odd flap techniques are know to me for water flying. I would happily demonstrate them, but will not describe them here. I don't want my conscience dealing with someone wrecking a plane because they tries something I wrote here, without the benefit of qualified, prepared supervision.
Changing flap settings during takeoff introduces simulaineous distraction, and change in flying qualities, neither of which are appropriate during a takeoff by a pilot who is new, or new to type.
New pilots are reminded that just because you read that people do things in planes, don't assume you can get away with it too! You start your flying career with a full bag of luck, and an empty bag of experience. The trick is to use your judgement to fill the experience bag, before you empty the bag of luck!
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Pilot Dar, a very good post. I agree with everything you say.
The point of my previous ( Tongue in cheek, < I did say the safest way to get a heavy PA28 out of a short field is on the back of a truck>) post is to get poeple used to thinking outside of the box and learn extra skills such as those that you have developed over the years.
I made a point of advising people not to try it on their own,but untill anyone learns these sort of things they will not develop their airmanship.
It grieves me though when some poeple with no experience come on here and shout down others.
Several people have posted to the effect that what I have said cannot/shouldnot be done despite evidence from others saying they use this tecnique. Are we then liars?
However perhaps I would have been better saying that the tecnique is really more of a softfield tecnique than shortfield.
I once had the dubious pleasure of sitting next to a sanctimonious pilot that did " everything by the book" and was a legend in his own mind.Having got the weather briefing, done a c of a for the preflight and reread the checklist 4 times we started the take off. He announced that in accordance with the POH we would start the take off with full aieleron deflection as there was a brisk crosswind which from his weather brief was to be from the left. As we started to roll I nudged his elbow and pointed to the windsock which clearly showed a strong wind from the right. This went unnoticed and as the wing slowly lifted and we started to ground loop I took control. When we got to approx 300ft I gave him the controls back and he said those famous words " well I don't know what happened there, I did everything by the book."
That was over 20 yrs ago, the same pilot now has about 160 hrs in one type but is never backwoods at coming forward with advise for others as he still thinks of himself as being a superior pilot because " he always does everything by the book".
The point of my previous ( Tongue in cheek, < I did say the safest way to get a heavy PA28 out of a short field is on the back of a truck>) post is to get poeple used to thinking outside of the box and learn extra skills such as those that you have developed over the years.
I made a point of advising people not to try it on their own,but untill anyone learns these sort of things they will not develop their airmanship.
It grieves me though when some poeple with no experience come on here and shout down others.
Several people have posted to the effect that what I have said cannot/shouldnot be done despite evidence from others saying they use this tecnique. Are we then liars?
However perhaps I would have been better saying that the tecnique is really more of a softfield tecnique than shortfield.
I once had the dubious pleasure of sitting next to a sanctimonious pilot that did " everything by the book" and was a legend in his own mind.Having got the weather briefing, done a c of a for the preflight and reread the checklist 4 times we started the take off. He announced that in accordance with the POH we would start the take off with full aieleron deflection as there was a brisk crosswind which from his weather brief was to be from the left. As we started to roll I nudged his elbow and pointed to the windsock which clearly showed a strong wind from the right. This went unnoticed and as the wing slowly lifted and we started to ground loop I took control. When we got to approx 300ft I gave him the controls back and he said those famous words " well I don't know what happened there, I did everything by the book."
That was over 20 yrs ago, the same pilot now has about 160 hrs in one type but is never backwoods at coming forward with advise for others as he still thinks of himself as being a superior pilot because " he always does everything by the book".
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Several people have posted to the effect that what I have said cannot/shouldnot be done despite evidence from others saying they use this tecnique. Are we then liars?
However perhaps I would have been better saying that the tecnique is really more of a softfield tecnique than shortfield.
However perhaps I would have been better saying that the tecnique is really more of a softfield tecnique than shortfield.
I have used the technique of running clean and then pulling in the first stage of flap many times.
What I question is the technique of yanking in full flap.
As you know the most lift comes in early stages of flap the most Drag and least lift comes with subsequent stages and especially full flap in most cases.
Whether the benefit of a tiny bit more lift compared to the negative of a massive amount of drag and the perils that carries is worth it?
Yes there is a danger that some inexperienced pilot will read what he sees here and try it for himself.
Can you explain the science or thinking behind your technique of full flap?
Pace ATP 4000 hrs multi and jet rated
Last edited by Pace; 2nd Apr 2009 at 12:40.
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Hatzflyer,
I completely agree. "The book" is the commonly agreed, best compromize between performance and safety for the average pilot skill. Once an aircarft is experienced in service, "tribal knowledge" will be developed by it's most experienced and adventurous operators. That knowledge will most certainly be techniques and capabilities beyond what the flight manual presents.
Prior to information whizzing around hyperspace, the only source of tribal knowledge, was it be in the tribe (if they'd let you in). Now we have "who knows?", reading all of this, and becoming very well informed, but no better skilled - it worries me.
Last year I demonstrated some advanced techinques in my STOL Cessna 150 to a 200 hour CPL ME IFR PPRuNer who came to visit. I was amazed at how much this pilot had not been taught. This pilot was apparently stunned by how much there was now to learn, that had never been imagined!
My task earlier this month was to vet and draft flight manual wording for a new variant of a well known new twin. With some of the wording in place, we were flight testing to validate the procedures. After flight testing, we changed the document even more - so a new pilot would not hurt themselves, if they did it the way the book says. During the testing, (and by prior planning) it became absolutely unavoidable to have to fly with a L/R fuel imbalance three times the maximum permitted by the book. It worked fine, but we're going to leave the flight manual as is...
The minute the super pilot get's it wrong, he'll be looking for someone to blame. I'm not going to set my self up for that!
Pilot DAR
I completely agree. "The book" is the commonly agreed, best compromize between performance and safety for the average pilot skill. Once an aircarft is experienced in service, "tribal knowledge" will be developed by it's most experienced and adventurous operators. That knowledge will most certainly be techniques and capabilities beyond what the flight manual presents.
Prior to information whizzing around hyperspace, the only source of tribal knowledge, was it be in the tribe (if they'd let you in). Now we have "who knows?", reading all of this, and becoming very well informed, but no better skilled - it worries me.
Last year I demonstrated some advanced techinques in my STOL Cessna 150 to a 200 hour CPL ME IFR PPRuNer who came to visit. I was amazed at how much this pilot had not been taught. This pilot was apparently stunned by how much there was now to learn, that had never been imagined!
My task earlier this month was to vet and draft flight manual wording for a new variant of a well known new twin. With some of the wording in place, we were flight testing to validate the procedures. After flight testing, we changed the document even more - so a new pilot would not hurt themselves, if they did it the way the book says. During the testing, (and by prior planning) it became absolutely unavoidable to have to fly with a L/R fuel imbalance three times the maximum permitted by the book. It worked fine, but we're going to leave the flight manual as is...
The minute the super pilot get's it wrong, he'll be looking for someone to blame. I'm not going to set my self up for that!
Pilot DAR
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I already have to a degree but to repeat and add a none too technical reason its because it is really a soft field tecnique. By pulling full flap, due to the proximity to the ground,the flaps act effectively as an air dam and provide a cushion of trapped air which pops the wheels out of the mud, there by relieving the extra drag on the wheels and allowing the plane to accellerate to a speed at which flight then becomes possible (which it would not otherwise do.) albeit in a semi stalled condition. This is where the skill comes in as eluded to in my previous post ref. raising flaps slowly to trade drag for speed and then climb(strictly in that order!).
It is of no use on a long tarmac runway obviously,where as you correctly say they would increase drag. Hence my reference to muddy fields and cautions about skidding. Perhaps I did not make this clear in my previos post for which I apologise!
I have also used this tecnique in a Beach Sundowner.
This phenomonon was exploited by some aircraft designers that put belly flaps on their aircraft when plain or split flaps were the norm but this seems to have gone out of fashion with the more widespred use of better (eg. fowler type) flaps.
Edited..Obviously this tecnique will not work with high wing or electric flaps.
It is of no use on a long tarmac runway obviously,where as you correctly say they would increase drag. Hence my reference to muddy fields and cautions about skidding. Perhaps I did not make this clear in my previos post for which I apologise!
I have also used this tecnique in a Beach Sundowner.
This phenomonon was exploited by some aircraft designers that put belly flaps on their aircraft when plain or split flaps were the norm but this seems to have gone out of fashion with the more widespred use of better (eg. fowler type) flaps.
Edited..Obviously this tecnique will not work with high wing or electric flaps.
Last edited by hatzflyer; 2nd Apr 2009 at 13:19.
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Just keep in mind that there are two things to worry about: getting off the ground, and clearing obstacles. A PA28, especially the -140, is no Ferrari of the air. Your idea of full flap may work if there are no obstacles, but keep in mind that the time needed to clean up the aircraft to climb away may very well lengthen your distance to clear the theoretical 50' obstacle.
Nothing beats knowing your aircraft, and I have operated outside "the book" on numerous occasions, in a safe setting, to learn just what was possible in a pinch. I know how my aircraft operates in just about every configuration including in a spin (it is cleared for it, my Sundowner is one of the rare ones with the aerobatic kit installed). The field where I operate from is 5000 ft of asphalt but I also fly into a buddy's farm that is 3000 ft grass with a mountain at one end, and my home base is infested with deer, so being able to haul it off the ground early may be useful some day (I have manual flaps). But I don't think it should be routine unless you are very, very practiced at it. I do know for a fact with my Sundowner, without flap, any attempt to pull it into the air below 65 knots is futile and quite possibly dangerous, and it will definitely only increase your takeoff distance.
Nothing beats knowing your aircraft, and I have operated outside "the book" on numerous occasions, in a safe setting, to learn just what was possible in a pinch. I know how my aircraft operates in just about every configuration including in a spin (it is cleared for it, my Sundowner is one of the rare ones with the aerobatic kit installed). The field where I operate from is 5000 ft of asphalt but I also fly into a buddy's farm that is 3000 ft grass with a mountain at one end, and my home base is infested with deer, so being able to haul it off the ground early may be useful some day (I have manual flaps). But I don't think it should be routine unless you are very, very practiced at it. I do know for a fact with my Sundowner, without flap, any attempt to pull it into the air below 65 knots is futile and quite possibly dangerous, and it will definitely only increase your takeoff distance.
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Is it an illusion?
Hatzflyer
be careful that this idea of full flap is not an illusion.
Its not my intention to point score here as i can see an arguemnt for putting in first stage of flap to slightly shorten a takeoff roll.
First stage of flap may be advised in the POH for a short field takeoff technique.
Running clean till near rotation makes sense as you are using the published short field takeoff but keeping the aircraft clean until near rotation and then adding the lift with minimal flap drag this has to allow the aircraft to accelerate slightly quicker and at rotation you get the lift from first stage of flap.
Here is where I have a problem! in both cases first stage or full flap you are running to near rotation clean on soft or hard ground so there can be NO benefit until the point that the flap is applied.
In most cases the small extra lift generated by taking full flap is negated by the massive increase in drag compared to the large lift and small drag of first stage.
BUT! the illusion will be different! applying full flap will have two effects giving an ILLUSION of elevator type lift.
Firstly there will be a huge amount of drag. That will give an instant braking effect and a momentary deceleration. Couple that with all the flap lift and that will give an ILLUSION of springing into the air which will not be as prominent as with first stage.
Once in the air you are now saddled with huge drag, a reluctance to accelerate or climb and still in ground effect.
What I feel you are getting is braking and levitating kidding the mind into an illusion.
I bet if you put this to scrutiny you would not be getting what you think you are getting as it makes no scientific sense that I can think of.
As stated I am not trying to point score on you but to convince myself of your arguement and NO i am not known as a by the book pilot either
Pace
be careful that this idea of full flap is not an illusion.
Its not my intention to point score here as i can see an arguemnt for putting in first stage of flap to slightly shorten a takeoff roll.
First stage of flap may be advised in the POH for a short field takeoff technique.
Running clean till near rotation makes sense as you are using the published short field takeoff but keeping the aircraft clean until near rotation and then adding the lift with minimal flap drag this has to allow the aircraft to accelerate slightly quicker and at rotation you get the lift from first stage of flap.
Here is where I have a problem! in both cases first stage or full flap you are running to near rotation clean on soft or hard ground so there can be NO benefit until the point that the flap is applied.
In most cases the small extra lift generated by taking full flap is negated by the massive increase in drag compared to the large lift and small drag of first stage.
BUT! the illusion will be different! applying full flap will have two effects giving an ILLUSION of elevator type lift.
Firstly there will be a huge amount of drag. That will give an instant braking effect and a momentary deceleration. Couple that with all the flap lift and that will give an ILLUSION of springing into the air which will not be as prominent as with first stage.
Once in the air you are now saddled with huge drag, a reluctance to accelerate or climb and still in ground effect.
What I feel you are getting is braking and levitating kidding the mind into an illusion.
I bet if you put this to scrutiny you would not be getting what you think you are getting as it makes no scientific sense that I can think of.
As stated I am not trying to point score on you but to convince myself of your arguement and NO i am not known as a by the book pilot either
Pace
Last edited by Pace; 2nd Apr 2009 at 15:17.
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My flights out of less than 300yds of wet grass are no illusion I can assure you.
I am not in the habit of telling lies,and quite frankly am bored of poeple telling me I can't do something that I HAVE done many many times.Q.E.D.
I am not in the habit of telling lies,and quite frankly am bored of poeple telling me I can't do something that I HAVE done many many times.Q.E.D.
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My flights out of less than 300yds of wet grass are no illusion I can assure you.
I am not in the habit of telling lies,and quite frankly am bored of poeple telling me I can't do something that I HAVE done many many times.Q.E.D.
I am not in the habit of telling lies,and quite frankly am bored of poeple telling me I can't do something that I HAVE done many many times.Q.E.D.
There is no need to go defensive I am sure you are a very capable competant pilot and do go out of your 300 metre wet grass strip but what has that got to do with discussing the merits and validity of your technique?
I am trying to be convinced of it not to shoot it down. There is a difference
Pace
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Hatzflyer
I think the question is have you done the same thing with the first and second stages and what is the difference to performance.
As to 300 yards of wet grass in a PA28, that's a risk to far for me, but don't take it as criticism, just my own feeling.
I've done 360 metres in a C172 and was at the edge of my comfort envelope.
I think the question is have you done the same thing with the first and second stages and what is the difference to performance.
As to 300 yards of wet grass in a PA28, that's a risk to far for me, but don't take it as criticism, just my own feeling.
I've done 360 metres in a C172 and was at the edge of my comfort envelope.
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Pulling full flap during roll, is CRAZY - as last stage is mainly DRAG - and you don't want that.
Here technic used on a snowy runway in Norway - and did not need much rwy to get of the ground.
2 stages of flaps, brakes on - full power, stick fully pulled back - let go of breaks, increase in speed, as soon as lifts of forward level stick pressure to build up speed and climb.
You hear stall warner as you leave the ground, however did this in both C-172 and PA 28, same technic, was thought to me by norwegian SAS pilot mostly flying F50 on the west coast of Norway, snowy jungle weather.
You will leave ground at around 35 kts speed, important to release back pressure as you take off!
Here technic used on a snowy runway in Norway - and did not need much rwy to get of the ground.
2 stages of flaps, brakes on - full power, stick fully pulled back - let go of breaks, increase in speed, as soon as lifts of forward level stick pressure to build up speed and climb.
You hear stall warner as you leave the ground, however did this in both C-172 and PA 28, same technic, was thought to me by norwegian SAS pilot mostly flying F50 on the west coast of Norway, snowy jungle weather.
You will leave ground at around 35 kts speed, important to release back pressure as you take off!
Moderator
You will leave ground at around 35 kts speed, important to release back pressure as you take off!
There are some runways that some aircraft don't belong in. If that technique is required, the owner should be shopping for a STOL kit!
Non-approved use of the flaps might have some value in soft surface conditions, where space is not a problem, but if it's a short runway, I'd be doing what the book says, for fear of having to explain myself to the insurance company later!
There's a fine line between "let me help you learn" and "watch this". I no longer go on the "watch this" side..
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This is short soft field take of which I thought by a highly competent commercial pilot in Norway.
This is I believe what is in the "Book" for short soft field take offs, I just stated the fact that I was surprised to notice that the airplane left the ground at around 35kts.
I do think if you do a little more research you will discover that this probably the best technic to get of the ground in shortest possible time on a soft airfield.
As I also fly in the UK, I did ask some of my instructors regarding this, and they confirmed this to be the correct technic for this specific condition.
Why?
We was making the take off in 7 -8 cm of snow, yes we had a long runway, however the snow slows you down during your take of run, just as soft wet grass ground will. So you want to get the wheels of as soon as possible and then build up speed for further climb.
Most have heard the phrase to put back pressure before reaching rotating speed, at 1 stage flap you can rotate quite safely at around 50 kts, without flaps I would use 60 kts.
The 35kts I mentioned was on the C-172, what the PA 28 speed was I did not take note of.
The C-172 stall speed full flap is 33kts, no flap 44kts !
(on the PA 28 161, its 44kts and 50 kts)
If you are on a soft ground, you do not want the friction to slow you down to extend your take off run more then max required. Full back pressure on the stick, will make the aircraft fly itself just of the ground when sufficient speed V has been reached - and then without the friction of the soft runway to slow you any further you can build to safe climb speed, either Vx or Vy, whatever is required.
And with a bit of research you will discover this is not a magic secret crazy that the aircraft flyes itself of the ground at relative low speed - let me note it will also almost wind still conditions.
What was my big surprise was how low the speed was before it left the ground, and secondly how easy it was to do this kind of take off.
However you still need some clearing ahead to build up speed before you can start the climb, however you will build up this speed faster once you are airborne/off the ground.
Maybe it was 35 - 36 - 37 or 38 kts, at the moment it was not my major concern to get the speed readout exact, but I was surprised how low the speed was to get OFF the ground!
This is I believe what is in the "Book" for short soft field take offs, I just stated the fact that I was surprised to notice that the airplane left the ground at around 35kts.
I do think if you do a little more research you will discover that this probably the best technic to get of the ground in shortest possible time on a soft airfield.
As I also fly in the UK, I did ask some of my instructors regarding this, and they confirmed this to be the correct technic for this specific condition.
Why?
We was making the take off in 7 -8 cm of snow, yes we had a long runway, however the snow slows you down during your take of run, just as soft wet grass ground will. So you want to get the wheels of as soon as possible and then build up speed for further climb.
Most have heard the phrase to put back pressure before reaching rotating speed, at 1 stage flap you can rotate quite safely at around 50 kts, without flaps I would use 60 kts.
The 35kts I mentioned was on the C-172, what the PA 28 speed was I did not take note of.
The C-172 stall speed full flap is 33kts, no flap 44kts !
(on the PA 28 161, its 44kts and 50 kts)
If you are on a soft ground, you do not want the friction to slow you down to extend your take off run more then max required. Full back pressure on the stick, will make the aircraft fly itself just of the ground when sufficient speed V has been reached - and then without the friction of the soft runway to slow you any further you can build to safe climb speed, either Vx or Vy, whatever is required.
And with a bit of research you will discover this is not a magic secret crazy that the aircraft flyes itself of the ground at relative low speed - let me note it will also almost wind still conditions.
What was my big surprise was how low the speed was before it left the ground, and secondly how easy it was to do this kind of take off.
However you still need some clearing ahead to build up speed before you can start the climb, however you will build up this speed faster once you are airborne/off the ground.
Maybe it was 35 - 36 - 37 or 38 kts, at the moment it was not my major concern to get the speed readout exact, but I was surprised how low the speed was to get OFF the ground!
Last edited by tigermagicjohn; 2nd Apr 2009 at 19:01.
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Come on folks, some of us have been around a fair amount of time a few thousand hours in my case(no instructing and all on light aircraft) we dont advocate the use of full flap rotation on a PA-28 as a norm but when the sh*t hits the fan and you need to get over that ditch at Fenland for what ever reason its nice to know what happens when you select whatever method, it will work. No one in their right mind would expect the aircraft in this configuration to meet the 50 ft requirement but it would be better than being in the ditch. The only reason for full flap/two notches of flap is because for whatever, you have got it wrong. Experience tells you what can be done but only if you try it and practice. Most do not spin an aeroplane but its nice to know how to get out of one(showing my age)
Secondly, since I am in the mood, those of us with a reasonable number of hours under our belt must remember that there are those at the lower end of the scale who expect us to quote accurate facts
Not wishing to pick on anyone in particular but since it the post prior to this
Quote C-172 stalls at 33knots total rubbish without the rest of the data
All aircraft stalls depend on a number of facts such as obviously weight, power,angle of bank, the rigging of the aeroplane to name but a few. By the above criteria each aeroplane is an idividual and stalls at whatever that ASI indicated. Try stalling at Fenland then try at Reno in the same aeroplane
So folks facts only please my son may read this
Secondly, since I am in the mood, those of us with a reasonable number of hours under our belt must remember that there are those at the lower end of the scale who expect us to quote accurate facts
Not wishing to pick on anyone in particular but since it the post prior to this
Quote C-172 stalls at 33knots total rubbish without the rest of the data
All aircraft stalls depend on a number of facts such as obviously weight, power,angle of bank, the rigging of the aeroplane to name but a few. By the above criteria each aeroplane is an idividual and stalls at whatever that ASI indicated. Try stalling at Fenland then try at Reno in the same aeroplane
So folks facts only please my son may read this
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Yes these are the FACTS of reality!
These were the specific instructions given by a Captain of SAS, Scandinavien Airlines, flying F50 - on inland routes of Norway, in addition he is CPL instructor and boss of the local flying school, probably has around 20.000 hours, flying nationally in Norway - think he should know what he is speaking about?
On the other hand, stall speed are only given as guidance, of course we ALL should know the aircraft stall at a specific angle of attack, and not at specific speed!
This is how short soft field take of is thought at this flying school in Norway!
These were the specific instructions given by a Captain of SAS, Scandinavien Airlines, flying F50 - on inland routes of Norway, in addition he is CPL instructor and boss of the local flying school, probably has around 20.000 hours, flying nationally in Norway - think he should know what he is speaking about?
On the other hand, stall speed are only given as guidance, of course we ALL should know the aircraft stall at a specific angle of attack, and not at specific speed!
This is how short soft field take of is thought at this flying school in Norway!
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You hear stall warner as you leave the ground, however did this in both C-172 and PA 28, same technic, was thought to me by norwegian SAS pilot mostly flying F50 on the west coast of Norway, snowy jungle weather.
You will leave ground at around 35 kts speed, important to release back pressure as you take off!
You will leave ground at around 35 kts speed, important to release back pressure as you take off!
Trying to fly a PA28 at 35 kts close to the ground is a very bad idea.
Though it was not initially relevent, this video may now offer some insight to the discussion. It is a soft field (deep snow) technique I sometimes use, when runway length is not a factor. If I work at it, being off the ground at 30 kts can be safely done. This aircraft is STOL kitted:
C150 40 Flap Takeoff video by PilotDAR - Photobucket
Pilot DAR
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As I did mention, the approx. 35kts scenario was in the C-172, the PA 28 will be at little higher speed, however main principle, 2 stages flaps, Brakes on, Full power, stick pulled back to the max. - let go of the brakes and just wait until whatever speed the aircraft is of the ground, I agree on the PA 28 it will not be 35 kts, it will be a little higher, however this is what will get you fastest of the soft ground.
The scenario of setting full flaps from clean configuration during the roll does not make sense, the first thing one should do during a go around is to reduce the full flap to 2.nd stage flap, because 40 degree flaps is a drag flap - and will also pitch nose down, CG and CP will be moved - it basic like putting air brakes on. I think it is more an illusion that this improves the take off distance compaired to the POH guideline.
High flap setting also decreases the angle of attack for the stall, so you will stall at a smaller angle then in clean configuration, so the likelyhood of stall is also increased with this way of take off.
You are approaching rotation speed, slam 40 degrees of flaps, speed will decrease - aircraft will balloon up, and might reach critical angle of attack, which will be much lower with 40 degrees of flaps, you might stall in the baloon setting full flaps.
This thought that some people have is an illusion of the mind set, like the glide, when you on the best glide speed, it seems tempting to raise the nose, because you think you might glide longer, however the manufactur has tested the aircraft and set the speed for best glide, still some people might illude themselves that this is wrong too.
Any common sense - from knowing how full flaps work on approach, you put the large stage of flaps and the aircraft drops like a stone trough the air, how can that effect possibly be any good during a take off? It's fairly logical, and you should have learnt this during the studies of Principle of Flight ! ?
The scenario of setting full flaps from clean configuration during the roll does not make sense, the first thing one should do during a go around is to reduce the full flap to 2.nd stage flap, because 40 degree flaps is a drag flap - and will also pitch nose down, CG and CP will be moved - it basic like putting air brakes on. I think it is more an illusion that this improves the take off distance compaired to the POH guideline.
High flap setting also decreases the angle of attack for the stall, so you will stall at a smaller angle then in clean configuration, so the likelyhood of stall is also increased with this way of take off.
You are approaching rotation speed, slam 40 degrees of flaps, speed will decrease - aircraft will balloon up, and might reach critical angle of attack, which will be much lower with 40 degrees of flaps, you might stall in the baloon setting full flaps.
This thought that some people have is an illusion of the mind set, like the glide, when you on the best glide speed, it seems tempting to raise the nose, because you think you might glide longer, however the manufactur has tested the aircraft and set the speed for best glide, still some people might illude themselves that this is wrong too.
Any common sense - from knowing how full flaps work on approach, you put the large stage of flaps and the aircraft drops like a stone trough the air, how can that effect possibly be any good during a take off? It's fairly logical, and you should have learnt this during the studies of Principle of Flight ! ?