Engine quits - what approach speed
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Sedbergh - you said:
"e) That's why not leaving it too late and flying some kind of a circuit round the field to assess slope, surface, stock and obstructions can keep you alive."
For your average GA pilot who flogs around at between 2,000 and 3,000 feet on a QNH setting, how many of those pilots will have sufficient altitude after they have found a field to fly "some kind of a circuit" without power before they perform the forced landing?
York.ppl - in some situations, there are no options. You could develop your question by saying "ah yes, but under the wires is my tractor.......and if you carry too much speed into the field, there is this nasty ditch you also failed to see..."
The rule is: fly the aeroplane. If the way ahead is blocked, look to your left and right - you might find a much shorter field into which you can land but will probably run into the hedge at the end. However, it might just happen you end up with nowhere to turn. Sadly it happens.
"e) That's why not leaving it too late and flying some kind of a circuit round the field to assess slope, surface, stock and obstructions can keep you alive."
For your average GA pilot who flogs around at between 2,000 and 3,000 feet on a QNH setting, how many of those pilots will have sufficient altitude after they have found a field to fly "some kind of a circuit" without power before they perform the forced landing?
York.ppl - in some situations, there are no options. You could develop your question by saying "ah yes, but under the wires is my tractor.......and if you carry too much speed into the field, there is this nasty ditch you also failed to see..."
The rule is: fly the aeroplane. If the way ahead is blocked, look to your left and right - you might find a much shorter field into which you can land but will probably run into the hedge at the end. However, it might just happen you end up with nowhere to turn. Sadly it happens.
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My preferance would be to go under the wires.
I was faced with the above situation a few weeks ago while carring out a PFL. Didn't spot the wires 'till about 150ft .........was aiming one third into the said field and the wires were about 3/4 of the way into the field.
I could have easily landed and passed under the wires.....needless to say I went around straight away.
I think to glide at a faster speed as a rule could get you into trouble.
If you manage to arrive in your chosen field at the aim point a third in with an extra 10 knots or so, then in something like a PA 28, you can expect to float down the rest of the field all the way to the scene of the accident in the hedge row. How severe the accident is will depend on the nature of the hedge, but could be very serious if there are a some trees to collide with.
Remember every 5kts of speed you manage to get rid off, significantly reduces ground run after landing.
I was faced with the above situation a few weeks ago while carring out a PFL. Didn't spot the wires 'till about 150ft .........was aiming one third into the said field and the wires were about 3/4 of the way into the field.
I could have easily landed and passed under the wires.....needless to say I went around straight away.
I think to glide at a faster speed as a rule could get you into trouble.
If you manage to arrive in your chosen field at the aim point a third in with an extra 10 knots or so, then in something like a PA 28, you can expect to float down the rest of the field all the way to the scene of the accident in the hedge row. How severe the accident is will depend on the nature of the hedge, but could be very serious if there are a some trees to collide with.
Remember every 5kts of speed you manage to get rid off, significantly reduces ground run after landing.
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Thanks for the replies everyone, sorry for ranting at the start but sometimes in this forum you need to get rid of the egos and pedants early on to allow sensible debate.
Lots of sensible debate too , in my absence
foxmouth
Clearly there is enough excess speed there to hop over an obstruction.
Hence me wondering if a little excess speed might be a good thing.
Cblinton I read about your incedent and I have to say, it was an awsome piece of flying, you have my absolute respect.
So some excess speed is a good thing in some circumstances.
Which goes to prove how easy it is to miss them.
Thanks again everyone
Lots of sensible debate too , in my absence
foxmouth
he best glide is 73kts with a threshold of 70 but the stall is only 44kts full flap so you could comfortably pull up to 60 kts or less and still have an adequate margin.
Would it be fair to ask (without setting Yorks off on another rant )at what time a pilot starts to reduce from best glide speed to a more suitable touch-down speed? Would such a time be some distance before said wires, and therefore there may be the possibility that in fact there is no excess speed available to hop over the wires?
what Yorks has said above is the rule I applied when my engine went bang and it is because of this I won the CAA Safety Award and none of my passengers or people on the ground were hurt.
So some excess speed is a good thing in some circumstances.
Didn't spot the wires 'till about 150ft
Thanks again everyone
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I'd put the nose down whatever. No doubt it is human nature to pull up to avoid the wires, but I think you'll be putting yourself in far more danger. As you pull up and drag increases, your airspeed will bleed off very quickly. Inertia is also in a downward direction. Best to put the nose down, increase airspeed and then pull up after you have passed the wires. Besides, there is less for them to catch on on the upside of an aeroplane.
Could always leave the flaps out until you have it made, then if you come across a situation like this, wack in full flap and balloon over the top. You might even be able to avoid the Taj Mahal this way.Fate is the Hunter....
Could always leave the flaps out until you have it made, then if you come across a situation like this, wack in full flap and balloon over the top. You might even be able to avoid the Taj Mahal this way.Fate is the Hunter....
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Isn't this similar to the situation where the pilot lines up on final and finds that their approach is going to put them exactly into the near hedge?
Answer - reduce drag - get rid of whatever drag flap you have.
If this was discovered late on then the aircraft will be at the min-approach speed which is below best glide for most aircraft. Thus get back to best glide speed.
Finally, far batter to pancake under control than cut your head off with the wires so - dive at a point just short of the hedge (cables) convert speed to height and promptly lower the nose as the hedge(cables) are cleared.
To see how you will get on, try the exercise at height - dive to best glide +say 15Kt and pull up at a predetermined height until the airspeed reads Vs+5 before lowering the nose positively again.
Note height gained and the time taken from pull-up to push over (so that you can work out distance travelled).
Now for the important bit, after the nose is again lowered, establish level flight at just below the height you pulled up at and see how long you can maintain level flight before the stall and check the attitude - is it the touchdown attitude?.
Best to talk about these things and practice at a safe height than have to make it up when it does happen.
Regards,
DFC
Answer - reduce drag - get rid of whatever drag flap you have.
If this was discovered late on then the aircraft will be at the min-approach speed which is below best glide for most aircraft. Thus get back to best glide speed.
Finally, far batter to pancake under control than cut your head off with the wires so - dive at a point just short of the hedge (cables) convert speed to height and promptly lower the nose as the hedge(cables) are cleared.
To see how you will get on, try the exercise at height - dive to best glide +say 15Kt and pull up at a predetermined height until the airspeed reads Vs+5 before lowering the nose positively again.
Note height gained and the time taken from pull-up to push over (so that you can work out distance travelled).
Now for the important bit, after the nose is again lowered, establish level flight at just below the height you pulled up at and see how long you can maintain level flight before the stall and check the attitude - is it the touchdown attitude?.
Best to talk about these things and practice at a safe height than have to make it up when it does happen.
Regards,
DFC
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Sedbergh is right
you certainly won't see any wires and you may not see poles but the islands around the pole bases are often easy to spot because they are very different from the rest of the field (try looking the next time you fly)
Its also worth looking at the bigger picture around your chosen field - that farm house 2 fields away is bound to have wires going to it from somewhere and any field boundry with a road running along it is highly suspicious
an obstruction on the approach will displace your touch down point by a minimum of 10 times the height of the obstruction (30 foot tree on the boundry puts you at least 100 yards into the field even if the field is 110 yards long !)
enjoy a few minutes obstruction spotting next time you fly !!
PS sometimes with fields s**t just happens - I went "aux vaches" into a young field of beans this summer and what i thought was a flock of birds turned out to be a forest of fence posts with tesco shopping bags tied on top of them - fortunately knowing s**t happens i had decided to avoid them anyway
perhaps the next discussion could be on how to spot electric fences !!
you certainly won't see any wires and you may not see poles but the islands around the pole bases are often easy to spot because they are very different from the rest of the field (try looking the next time you fly)
Its also worth looking at the bigger picture around your chosen field - that farm house 2 fields away is bound to have wires going to it from somewhere and any field boundry with a road running along it is highly suspicious
an obstruction on the approach will displace your touch down point by a minimum of 10 times the height of the obstruction (30 foot tree on the boundry puts you at least 100 yards into the field even if the field is 110 yards long !)
enjoy a few minutes obstruction spotting next time you fly !!
PS sometimes with fields s**t just happens - I went "aux vaches" into a young field of beans this summer and what i thought was a flock of birds turned out to be a forest of fence posts with tesco shopping bags tied on top of them - fortunately knowing s**t happens i had decided to avoid them anyway
perhaps the next discussion could be on how to spot electric fences !!
Avoid imitations
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Yorks.ppl,
I'm not sure there is a single answer to your question because each occasion would present its own difficulties. However, from experience gained during a few thousand hours flying (and training others to fly) at 50-100 feet agl in Support Helicopters, a few hundred of flying single engine jets at low level and instruction in SEP types, I've had a few very close shaves with wires myself. I would like to add a couple of things for you to ponder:
I personally lost four helicopter colleagues to wire strikes, one aircraft hitting large wires, the other hitting quite small ones. Another heli ex colleague, who frequents this website, got his aircraft entangled at very low speed, tried to back off the wire but it broke, flew up and went through the main rotors. They all survived. Doubly lucky because there was a ground threat from enemy action in his case. (Actually triple lucky, he also survived being hit in the face on another occasion by a large seagull that came through his windscreen during a low level flight).
You may or may not see the wires themselves and you may have very little or no time to react if you don't see the poles. Obviously, the secret during a forced landing is to look for the supporting poles early on, as we already know. This would give you the best fighting chance because you might have time to choose another field....
Suddenly faced with wires in your flightpath, you will have no idea in the few seconds whether they are going to break before your aircraft does.
You will probably act by instinct...
I also lost a very good friend and colleague, a fellow RAF QFI, to an SEP accident involving wires. When his engine failed, he did not see the wires across the near end of the field because the poles were hidden in trees (there was just a single span across the field).
The field was very small by UK standards, unfortunately he had no larger field to go for. On very short finals he apparently spotted the wires and tried to go under them. He did so, but unfortunately, he may have over-reacted and lowered the nose too far, because the wire was only 30 feet agl. What he probably thought was a hedge was actually a stone bank with a hedge growing on it. He hit it and was killed outright.
All I can say is that it might, in his case, have been better to have accepted the risk and flown into the wire but who knows for sure? Had he gone through the far hedge he might also have survived.
All told, I think the priority should be to get into the field. I would rather go through the far hedge at low speed than hit the near one at flying speed.
But don't carry extra speed into the field because that is what will kill you.
I'm not sure there is a single answer to your question because each occasion would present its own difficulties. However, from experience gained during a few thousand hours flying (and training others to fly) at 50-100 feet agl in Support Helicopters, a few hundred of flying single engine jets at low level and instruction in SEP types, I've had a few very close shaves with wires myself. I would like to add a couple of things for you to ponder:
I personally lost four helicopter colleagues to wire strikes, one aircraft hitting large wires, the other hitting quite small ones. Another heli ex colleague, who frequents this website, got his aircraft entangled at very low speed, tried to back off the wire but it broke, flew up and went through the main rotors. They all survived. Doubly lucky because there was a ground threat from enemy action in his case. (Actually triple lucky, he also survived being hit in the face on another occasion by a large seagull that came through his windscreen during a low level flight).
You may or may not see the wires themselves and you may have very little or no time to react if you don't see the poles. Obviously, the secret during a forced landing is to look for the supporting poles early on, as we already know. This would give you the best fighting chance because you might have time to choose another field....
Suddenly faced with wires in your flightpath, you will have no idea in the few seconds whether they are going to break before your aircraft does.
You will probably act by instinct...
I also lost a very good friend and colleague, a fellow RAF QFI, to an SEP accident involving wires. When his engine failed, he did not see the wires across the near end of the field because the poles were hidden in trees (there was just a single span across the field).
The field was very small by UK standards, unfortunately he had no larger field to go for. On very short finals he apparently spotted the wires and tried to go under them. He did so, but unfortunately, he may have over-reacted and lowered the nose too far, because the wire was only 30 feet agl. What he probably thought was a hedge was actually a stone bank with a hedge growing on it. He hit it and was killed outright.
All I can say is that it might, in his case, have been better to have accepted the risk and flown into the wire but who knows for sure? Had he gone through the far hedge he might also have survived.
All told, I think the priority should be to get into the field. I would rather go through the far hedge at low speed than hit the near one at flying speed.
But don't carry extra speed into the field because that is what will kill you.
Last edited by ShyTorque; 15th Dec 2005 at 16:04.
