Badly judged FL, how to survive?
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It is worth remembering that even a 'brick wall' has more deceleration distance than stalling onto the ground (your seat will only collapse a few inches whereas the nose probably has 3-4 feet of give) and your body generally survives spin loading very poorly. 20 feet of crash way gives roughly the same body load as hitting the ground in a 1000ft/min stall descent. This is why the doctor in Shoreham walked away after crashing into the house. Strategies like stall descent, spin through the clouds and recover, etc. are for novel writers not for real life.
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When I was gliding in the 80’s it was common practice to use s turns, but people were dying as it was causing them to spin. The BGA carried out a study and the advice was changed to side slip and not UNDER ANY CURCUMSTANCES to use S turns. I have been out of gliding for some time, but I thought I would pass this on.
Rod1
Rod1
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I agree with Rod1
I also used to glide in the 80s. It is a pity that a/c are not fitted with speed limiting airbrakes. An instructor once demonstrated a technique to me, 1000ft over the trees at the boundary, pull into a stall, as the nose dropped pull full brakes, stand on the rudder pedals almost vertical, max 70knots to 200ft, round out, & close the brakes to land as required from about 80yds inside the fence. Estimate the 200ft because the alt took a while to catch up! (A.S.K 13). It probably wouldn't work in a modern glass ship.
I also used to glide in the 80s. It is a pity that a/c are not fitted with speed limiting airbrakes. An instructor once demonstrated a technique to me, 1000ft over the trees at the boundary, pull into a stall, as the nose dropped pull full brakes, stand on the rudder pedals almost vertical, max 70knots to 200ft, round out, & close the brakes to land as required from about 80yds inside the fence. Estimate the 200ft because the alt took a while to catch up! (A.S.K 13). It probably wouldn't work in a modern glass ship.
The Original Whirly
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At a CAA safety evening a couple of years ago, we were told that if you can't land safely in a field, "Hit the softest object you can find at the lowest possible speed".
I remember hearing of a pilot who had engine failure over a city centre. He apparently (this is going to sound unbelievable) calmly flew through an office block window, taking off the wings but making a controlled landing, and walked away with only minor injuries.
I've also read that microlight landing accidents are rarely fatal because they tend to be at low speed.
Moral of all of the above - land at the lowest safe speed you can, under control, and you'll probably walk away. Stall or spin and you'll probably die.
I remember hearing of a pilot who had engine failure over a city centre. He apparently (this is going to sound unbelievable) calmly flew through an office block window, taking off the wings but making a controlled landing, and walked away with only minor injuries.
I've also read that microlight landing accidents are rarely fatal because they tend to be at low speed.
Moral of all of the above - land at the lowest safe speed you can, under control, and you'll probably walk away. Stall or spin and you'll probably die.
Pompey till I die
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IF there is only one "field" into which a landing would be remotely possible in your hypothetical scenerio and the alternatives are houses, then more dramatic solutions might be justified, but again the type of aircraft may be a factor.
SO...i have to ask, if you have trimmed to the correct speed, then why should you arrive at any field at the wrong speed
The Original Foot
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S Turns
I was taught that S Turns were a good way of loosing height if you needed to and you were stuck and provided an more aggressive way of loosing height. S Truns effectively mean you have to travel through more air to reach your destination. I was also taught, however, that you have keep your airspeed up, so a good shove forward on the yoke generally corresponds with these moves.
As a self confessed master of overshooting runways! I usually know quite a way up that an overshoot is coming and in a pfl situation I would act then and decisively to keep myself out of the wall. (Assuming I had forgotten my tin of nervergetyourselfintothat).
I think these hypothetcial discussions are useful and interesting points for a discussion board. I am now going to suggest if I was low and fast - how about planting the tail or wing into the field to effect a controlled crash. Or if there were a nice couple of trees at the other end of the field pointing the middle of my aircraft between the two. (Worked for James Bond in Golden Eye!)
I fully understand that such a suggestion means I should go and spend the rest of the year with an instructor, practise more. I am answering the question - what would I do if I was there...
As a self confessed master of overshooting runways! I usually know quite a way up that an overshoot is coming and in a pfl situation I would act then and decisively to keep myself out of the wall. (Assuming I had forgotten my tin of nervergetyourselfintothat).
I think these hypothetcial discussions are useful and interesting points for a discussion board. I am now going to suggest if I was low and fast - how about planting the tail or wing into the field to effect a controlled crash. Or if there were a nice couple of trees at the other end of the field pointing the middle of my aircraft between the two. (Worked for James Bond in Golden Eye!)
I fully understand that such a suggestion means I should go and spend the rest of the year with an instructor, practise more. I am answering the question - what would I do if I was there...
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IF there is only one "field" into which a landing would be remotely possible in your hypothetical scenerio and the alternatives are houses, then more dramatic solutions might be justified, but again the type of aircraft may be a factor.
Sounds like you are flying illegally, having broken Rule 5. Isn't it 1000ft or high enough to glide clear of built up areas, which ever is the higher ?
Not necessarly. Perhaps there were a number of options available at the time of engine failure, but by the time the pilot realised that they had messed up the approach (and perhaps field selection) their altitude had reduced to a point where the other options were no longer available.
dp
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A number of options have been mentioned, side slipping,S turns; another one that no one has mentioned is fishtailing - keep your speed and kick rudder left/right/left as much as you need - height will drop off very rapidly. Whichever method you use try it first with an instructor or someone who knows what they are doing.
Thread Starter
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Again many thanks for responses. It is a hypothetical scenario, but as Fuji says s$..t happens and it is good to have options.
Discussed this with my instructor who came up with a novel plan (as well as suggesting a bit of normal PFL practice). The Robin ATL has small drag flaps which move very quickly. We plan to set up a glide approach using best glide speed and 1/2 flap. If all goes well leave the flaps as set. If undershooting pull in the flaps, if overshooting put out full flap. Effectively using the flaps like a gliders speedbrakes. I take the point that this might be a way of compensating for my lack of recency, but it does seem like a useful exercise.
Discussed this with my instructor who came up with a novel plan (as well as suggesting a bit of normal PFL practice). The Robin ATL has small drag flaps which move very quickly. We plan to set up a glide approach using best glide speed and 1/2 flap. If all goes well leave the flaps as set. If undershooting pull in the flaps, if overshooting put out full flap. Effectively using the flaps like a gliders speedbrakes. I take the point that this might be a way of compensating for my lack of recency, but it does seem like a useful exercise.
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The Robin ATL has small drag flaps which move very quickly. We plan to set up a glide approach using best glide speed and 1/2 flap. If all goes well leave the flaps as set. If undershooting pull in the flaps, if overshooting put out full flap.
I've been told that once you have the flap on, pulling them in will result in sink - which you will probably not want if you're undershooting anyway.
I fly a PA28 - so is this due to aircraft differences or instructor differences???
I'm interested in this, as I've missed a fair bit of flying recently and my PFL's have suffered as a result.
My solution to the too high scenario - rightly or wrongly - is sideslip.... as soon as I recognise the problem, to get rid of the height. But the PA28 can do that.
If I was too low - pray!!!!!!!!!
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If all else fails..............
Just make sure that you are on the ground before you hit something, it is invariably safer to hit something at ground speed than air speed.
Just make sure that you are on the ground before you hit something, it is invariably safer to hit something at ground speed than air speed.
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I also can't afford as many hours as I would like / need.
BUT
For the price of 4 hours I have just had a full week at Lasham where every landing is a PFL.
Techniques and attitudes are a revelation, and a completely different world from my gliding solos of yore.
Has totally opened my eyes to PFL possibilities and was also VERY challenging.
SD
PS - side slips are my fave.
BUT
For the price of 4 hours I have just had a full week at Lasham where every landing is a PFL.
Techniques and attitudes are a revelation, and a completely different world from my gliding solos of yore.
Has totally opened my eyes to PFL possibilities and was also VERY challenging.
SD
PS - side slips are my fave.
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Mad Girl
I always approach too high with full flap and then slip off the extra height. It is then very unlikely you will get too low, provided you aim 1/3 of the way in. In most aircraft a side slip is a very useful tool.
Rod1
I always approach too high with full flap and then slip off the extra height. It is then very unlikely you will get too low, provided you aim 1/3 of the way in. In most aircraft a side slip is a very useful tool.
Rod1
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"I also used to glide in the 80s. It is a pity that a/c are not fitted with speed limiting airbrakes. An instructor once demonstrated a technique to me, 1000ft over the trees at the boundary, pull into a stall, as the nose dropped pull full brakes, stand on the rudder pedals almost vertical, max 70knots to 200ft, round out, & close the brakes to land as required from about 80yds inside the fence. Estimate the 200ft because the alt took a while to catch up! (A.S.K 13). It probably wouldn't work in a modern glass ship."
My instructor demo'ed this from 2000'. if I hadn't been in the front seat and seen it all, I wouldn't have believed it. This was in a Puchacz (GF 2 seat trainer).
We started at 2000' above the threshold hedge, came down vertically (it felt like) under full control, and the ground roll stopped about 75 yards after the same hedge.
Amazing.
I have to say that much of the glider pilot's bravado viz "every landing's a forced landing, old boy" would look a bit silly without the extremely effective air-brakes fitted to most gliders, combined with an excellent glide ratio (natcherly).
My instructor demo'ed this from 2000'. if I hadn't been in the front seat and seen it all, I wouldn't have believed it. This was in a Puchacz (GF 2 seat trainer).
We started at 2000' above the threshold hedge, came down vertically (it felt like) under full control, and the ground roll stopped about 75 yards after the same hedge.
Amazing.
I have to say that much of the glider pilot's bravado viz "every landing's a forced landing, old boy" would look a bit silly without the extremely effective air-brakes fitted to most gliders, combined with an excellent glide ratio (natcherly).
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Stuffing the nose down and fllying faster than best glide speed while dangling as much stuff off the aeroplane as you possibly can - full flap, gear, anything else you've got will cause you to bleed more energy than you'd lose by flying at best glide speed. True, you'll arrive at the ground with more airspeed than you would do at best glide, but you'll arrive significantly nearer the start of the field, and with less energy overall compared with the solid object at the other end - not my best piece of science, but you all know what I mean!
I fully appreciate it's a long way from ideal - yes, you'd ideally want to be flying your perfect approach at best glide into a perfect field, but we're talking hypothetical situations here, where you just HAVE to make it into THAT field from this particular combination of geographic and vertical position and airspeed.
Oh, and for god's sakes don't do a fully held off landing - if stopping distance is an issue stick it down so you have the benefit of rolling friction as well as aerodynamice braking. Yes, you risk breaking the gear, but again, we're talking worst case here - and to be honest, sliding it on its belly may give you some extra friction you'll appreciate! But don't bounce the bloody thing, potentially an issue if you're trying to plant the aeroplane onto terra firma at a possibly high airspeed.
As previously mentioned though - sidelsip is a powerful thing, anyone not familiar/current with it should go see an instructor and change that state!
I fully appreciate it's a long way from ideal - yes, you'd ideally want to be flying your perfect approach at best glide into a perfect field, but we're talking hypothetical situations here, where you just HAVE to make it into THAT field from this particular combination of geographic and vertical position and airspeed.
Oh, and for god's sakes don't do a fully held off landing - if stopping distance is an issue stick it down so you have the benefit of rolling friction as well as aerodynamice braking. Yes, you risk breaking the gear, but again, we're talking worst case here - and to be honest, sliding it on its belly may give you some extra friction you'll appreciate! But don't bounce the bloody thing, potentially an issue if you're trying to plant the aeroplane onto terra firma at a possibly high airspeed.
As previously mentioned though - sidelsip is a powerful thing, anyone not familiar/current with it should go see an instructor and change that state!
sunday driver
Was that a residential course? How many in the group? Winch / aerotow - or both? How many circuits did you get?
FBW
For the price of 4 hours I have just had a full week at Lasham
FBW
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Some very 'interesting' comments on this thread... particularly as a glider pilot who's doing a PPL at the moment..
Typical modern glass ships approach a *LOT* flatter than the 150 I'm flying.. and gain / retain energy a lot better too - we don't have it *that* easy
That aside, some comments - the 3 pretty much cover what I'd be trying to do in order of action. Maybe I'm wrong!
Powered pilots (generalisation) tend to fly regular rectangular circuits. Gliders fly a continuously variable circuit, judging the angle all the way - high? push out, fly base angled a little away etc. Low, cramp it in, and in extreme cases, turn in early, land 1/2 way up the runway. Or even crosswind. Better to have an accident on the ground than one in the air which will eventually meet the ground. Once in PFL mode, I'm treating it like a glider - no complaints from my instructor so far.
Using flaps isn't novel! I've been taught to extend progressively to control the approach once you're sure you're in (i.e. above glide), and aim to land on full flap. Retraction is strictly against the 'book', but instructor suggests it can be considered if desparate, so long as it's done well above clean stall speed, and a bit at a time. Anything you throw out that increases drag will worsen the glide. C150 on 40degrees of flap assumes the glide angle of a somewhat homesick brick at 60kt.
I would not want to be anywhere near stall, anywhere near the ground. You're vulnerable to gusts, turbulence, and lord knows what. *Gliding* training is if faced with an over small field to get it on the floor (fly it on) and brake hard. If the fence is looming, kick in the rudder, put a wing down and ground loop - all that energy that goes into pulling the wings off, rolling, and otherwise remodelling the airframe is dissipated in a way that doesn't involve the human body in a sudden stop.
Never had to do it. Sounds good in theory, but anyone who's been in a ground loop may disagree
Typical modern glass ships approach a *LOT* flatter than the 150 I'm flying.. and gain / retain energy a lot better too - we don't have it *that* easy
That aside, some comments - the 3 pretty much cover what I'd be trying to do in order of action. Maybe I'm wrong!
Powered pilots (generalisation) tend to fly regular rectangular circuits. Gliders fly a continuously variable circuit, judging the angle all the way - high? push out, fly base angled a little away etc. Low, cramp it in, and in extreme cases, turn in early, land 1/2 way up the runway. Or even crosswind. Better to have an accident on the ground than one in the air which will eventually meet the ground. Once in PFL mode, I'm treating it like a glider - no complaints from my instructor so far.
Using flaps isn't novel! I've been taught to extend progressively to control the approach once you're sure you're in (i.e. above glide), and aim to land on full flap. Retraction is strictly against the 'book', but instructor suggests it can be considered if desparate, so long as it's done well above clean stall speed, and a bit at a time. Anything you throw out that increases drag will worsen the glide. C150 on 40degrees of flap assumes the glide angle of a somewhat homesick brick at 60kt.
I would not want to be anywhere near stall, anywhere near the ground. You're vulnerable to gusts, turbulence, and lord knows what. *Gliding* training is if faced with an over small field to get it on the floor (fly it on) and brake hard. If the fence is looming, kick in the rudder, put a wing down and ground loop - all that energy that goes into pulling the wings off, rolling, and otherwise remodelling the airframe is dissipated in a way that doesn't involve the human body in a sudden stop.
Never had to do it. Sounds good in theory, but anyone who's been in a ground loop may disagree
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Fly-by-wife
£500 got me
5 days full-time non-residential (we live 45 mins from Lasham)
1 wet day with one aero-tow and sessions on their excellent simulator
4 glorious days with 4 aerotows, 24 winch launches
Flight times ranging from 1 minute to 1 hour
Included an end-of course hour in a DG1000 with aeros and more
Group of four students of mixed abilities with 2 dedicated excellent instructors
Side benefits are a first class club house, a good restaurant, a nice bar, lots of aviation nostalgia, more laughs than several evenings in Jongleurs.
Oh yes, it was quite hard work, physically and intellectually (dumping those nice square circuits and learning what those convenient footrests are really for)
Mrs Driver has often said she'd like to try flying, so we went together (another 500 quid but cheaper than a week's self catering holiday). We're so impressed that today I'm off to book another week.
SD
£500 got me
5 days full-time non-residential (we live 45 mins from Lasham)
1 wet day with one aero-tow and sessions on their excellent simulator
4 glorious days with 4 aerotows, 24 winch launches
Flight times ranging from 1 minute to 1 hour
Included an end-of course hour in a DG1000 with aeros and more
Group of four students of mixed abilities with 2 dedicated excellent instructors
Side benefits are a first class club house, a good restaurant, a nice bar, lots of aviation nostalgia, more laughs than several evenings in Jongleurs.
Oh yes, it was quite hard work, physically and intellectually (dumping those nice square circuits and learning what those convenient footrests are really for)
Mrs Driver has often said she'd like to try flying, so we went together (another 500 quid but cheaper than a week's self catering holiday). We're so impressed that today I'm off to book another week.
SD
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I've been told that once you have the flap on, pulling them in will result in sink
That's true in the short term but the overall effect is that the glide performance (the distance you will travel before hitting the ground) will improve.
What you have to watch is stall speeds. Let's say Vs at max flap is 55kt but with half flap is 70kt. If you are doing 65kt and pull the flap in, you will stall, so that wasn't a good idea! But if you are doing 90kt then it's fine. That's why knowing "the numbers" for the type is desirable.
It would take a lot of ba11s to pull in flaps and gear to improve one's glide, when already close to the ground.
The converse also applies: let's say you are gliding at 90kt. My Vs is 95 so for me that's reasonable. Let's say that very close in I am not quite going to make it over some hedge. Pulling in full flap drops my Vs to 59kt (or less if below MTOW) and together with the balooning this will allow a significant trade from speed to height - a very short term thing which amounts to flogging the family silver.
Much depends on circumstances of course. In a desperate case of having to plant the thing in a tiny spot I would land gear up and go full-flap on short final - pushing down on the yoke to prevent it balooning up which is what happens on my type when going full flap. I hope to never have to do this - simply due to the way I fly, as high as possible, but it may be necessary in mountainous terrain where there are usually plenty of little fields down below.
In any lesser emergency I would land gear down, with a stabilised approach, into a spot picked early on. If done right, it will reduce a minimum-£30,000 insurance claim (of a gear up) to the cost of getting the thing out of there - £3,000 or so if the wings have to come off & a trailer, or nothing if it can be flown out.
The whole forced-landing business is very debatable and no two people will give the same answer.
Some teach the "RAF method" which is to pick a field down below, aim for left base at 1500ft AGL and glide in from there. Some would prefer to pick a series of fields straight ahead (if they exist) and that is certainly the easiest one to do - except that they can't be inspected beforehand the way you can inspect one directly below. But what the hell; this is an emergency...
I think a good way to get reasonably good at this, in your own time and under no pressure, is to - subject to traffic - try to not fly the square circuits but fly ovals, and make the base leg a glide approach on little or no power.
That's true in the short term but the overall effect is that the glide performance (the distance you will travel before hitting the ground) will improve.
What you have to watch is stall speeds. Let's say Vs at max flap is 55kt but with half flap is 70kt. If you are doing 65kt and pull the flap in, you will stall, so that wasn't a good idea! But if you are doing 90kt then it's fine. That's why knowing "the numbers" for the type is desirable.
It would take a lot of ba11s to pull in flaps and gear to improve one's glide, when already close to the ground.
The converse also applies: let's say you are gliding at 90kt. My Vs is 95 so for me that's reasonable. Let's say that very close in I am not quite going to make it over some hedge. Pulling in full flap drops my Vs to 59kt (or less if below MTOW) and together with the balooning this will allow a significant trade from speed to height - a very short term thing which amounts to flogging the family silver.
Much depends on circumstances of course. In a desperate case of having to plant the thing in a tiny spot I would land gear up and go full-flap on short final - pushing down on the yoke to prevent it balooning up which is what happens on my type when going full flap. I hope to never have to do this - simply due to the way I fly, as high as possible, but it may be necessary in mountainous terrain where there are usually plenty of little fields down below.
In any lesser emergency I would land gear down, with a stabilised approach, into a spot picked early on. If done right, it will reduce a minimum-£30,000 insurance claim (of a gear up) to the cost of getting the thing out of there - £3,000 or so if the wings have to come off & a trailer, or nothing if it can be flown out.
The whole forced-landing business is very debatable and no two people will give the same answer.
Some teach the "RAF method" which is to pick a field down below, aim for left base at 1500ft AGL and glide in from there. Some would prefer to pick a series of fields straight ahead (if they exist) and that is certainly the easiest one to do - except that they can't be inspected beforehand the way you can inspect one directly below. But what the hell; this is an emergency...
I think a good way to get reasonably good at this, in your own time and under no pressure, is to - subject to traffic - try to not fly the square circuits but fly ovals, and make the base leg a glide approach on little or no power.