Moruya crash 19/12/19
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Location: French Alps
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How are you going to convert speed to height if you're already at Best Glide Speed? Surely by slowing down your descent angle will increase (apart from the small yug effect when you pull back; "momentum" in a bug smasher??)? Now, if you were deliberately descending at faster than Best Glide, I could understand adjusting the aim point by slowing down. But if you don't have the capacity to slow down because you're already at Best Glide...
Regularly demonstrating the above flying and teaching mandatory dead stick techniques to PPL's.
You’ve got to ask yourself, why is this valuable piece of advice not in the emergency procedures section in the POH for every GA aircraft? I think I can guess why.
I'd agree that if you're a bit low on approach, you'll be better off lowering the nose to convert height to speed. You'll then enter ground effect with better chances that the extended hold off will allow you to plant the wheels farther.
Regularly demonstrating the above flying and teaching mandatory dead stick techniques to PPL's.
Regularly demonstrating the above flying and teaching mandatory dead stick techniques to PPL's.
You would have to have two identically configured aircraft starting at the exact same point in space, flying the two different profiles at the same time to see who went furtherest.
I don't want to comment on the Moruya accident because I wasn't in the aeroplane at the time and therefore don't have the first clue what happened or why. I'm not going to sit here and armchair judge a fellow pilot. But the concept of pushing into ground effect when you realise you are undershooting on short final is valid under some circumstances.
The first of these videos illustrates a scenario like aroa is alluding to, where the aircraft is low and slow, running out of energy and falling short without any spare airspeed. The second shows a more exagerated situation with plenty of energy to spare which probably didn't result in any better overall glide performance from the starting point, but it does illustrate just how dramatic the reduction in induced drag is.
It's not about being "better" than best glide speed. Overall, it isn't. The gain comes from the fact that in the initial pushover, the wing is unloaded with next to no induced drag for a few seconds, which gives you a small boost in momentum. Since the transition into ground effect from this pushover at this late stage in the approach takes only a few seconds, the higher parasite drag from the dive above best glide speed affacts you for only a small portion of the total remaining flight time and hence you get a net gain. It's not something to use as a standard approach plan, but it can be a useful dirty trick that you can pull if you realise that you're falling short and have nothing else left that you can do. The effect is more pronounced with high aspect ratio wings (e.g. gliders) but it works to an extent on any aircraft, more so if the prop is stationary (or at least, in coarse pitch) and not windmilling. Whether it's enough to be worth while depends on the specific aircraft type and configuration.
But again, I don't think it is all that helpful to speculate on why the guys in the 210 didn't make the field. Sometimes, sh!t happens. I'm pretty sure they didn't crash themselves into a tree for our entertainment, and in any case there could have been (and probably were) any number of distractions going on that we don't know about. Real world emergencies have a way of being a bit more full-on than the nice neat canned practice forced landing scenarios that most people base their supposed expertise on. So here's to just wishing them well for a swift recovery.
The first of these videos illustrates a scenario like aroa is alluding to, where the aircraft is low and slow, running out of energy and falling short without any spare airspeed. The second shows a more exagerated situation with plenty of energy to spare which probably didn't result in any better overall glide performance from the starting point, but it does illustrate just how dramatic the reduction in induced drag is.
It's not about being "better" than best glide speed. Overall, it isn't. The gain comes from the fact that in the initial pushover, the wing is unloaded with next to no induced drag for a few seconds, which gives you a small boost in momentum. Since the transition into ground effect from this pushover at this late stage in the approach takes only a few seconds, the higher parasite drag from the dive above best glide speed affacts you for only a small portion of the total remaining flight time and hence you get a net gain. It's not something to use as a standard approach plan, but it can be a useful dirty trick that you can pull if you realise that you're falling short and have nothing else left that you can do. The effect is more pronounced with high aspect ratio wings (e.g. gliders) but it works to an extent on any aircraft, more so if the prop is stationary (or at least, in coarse pitch) and not windmilling. Whether it's enough to be worth while depends on the specific aircraft type and configuration.
But again, I don't think it is all that helpful to speculate on why the guys in the 210 didn't make the field. Sometimes, sh!t happens. I'm pretty sure they didn't crash themselves into a tree for our entertainment, and in any case there could have been (and probably were) any number of distractions going on that we don't know about. Real world emergencies have a way of being a bit more full-on than the nice neat canned practice forced landing scenarios that most people base their supposed expertise on. So here's to just wishing them well for a swift recovery.
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Sudent pilots are required to be able to judge whether they are grossly under or overshooting.
Noting the aiming point is not where the wheels will make contact with ground, there is also some judgement at play managing the hold-off before touchdown.
If you can see on mid final that it looks like being a close thing, consider retracting the flap from full flap (if that is what you already had) to half flap. There may be a slight nose down pitch change but providing your approach speed is under control that is easy to counteract. With most light aircraft there is only 3-5 knots difference in stall speed between full and half flap but the reduction in drag can be significant.
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Not to mention another useful trick (assuming it hasn't been referred to earlier) with a single engine aircraft (ie non-feathering constant speed prop) is to pull full coarse on the pitch control to reduce ROD. Pitch control makes for a very effective drag brake - we used it routinely on parachute ops in years gone by.
I was under the impression that this Cessna C210 was a turbine engine modified aircraft with a Allison B17B engine or similar model engine in which case full feathering is not normally available in flight, only upon engine shutdown. (oil pressure)
Perhaps it would be the same engine STC as the A36 Bonanza modification.
Johnson & Johnson in the USA operate or at least used to, a Nomad on floats at the bosses lake house. This aircraft had modified engines so that full feathering was available with engines running on the ground/water.
Perhaps it would be the same engine STC as the A36 Bonanza modification.
Johnson & Johnson in the USA operate or at least used to, a Nomad on floats at the bosses lake house. This aircraft had modified engines so that full feathering was available with engines running on the ground/water.
I was under the impression that this Cessna C210 was a turbine engine modified aircraft with a Allison B17B engine or similar model engine in which case full feathering is not normally available in flight, only upon engine shutdown. (oil pressure)
Too much drag ie non feathered prop was not the issue here. The issue appears ( from the Flightradar24 track pic) to have been too much energy and not enough drag or judgment most likely both.
Too much drag ie non feathered prop was not the issue here. The issue appears ( from the Flightradar24 track pic) to have been too much energy and not enough drag or judgment most likely both
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Overshoot
[On 14 January 2010, a Cessna Aircraft Co. 208B Caravan, registered VH-NTQ, was en-route from Broome to Koolan Island, Western Australia (WA) at an altitude of about 9,500 ft, when the pilot noticed a drop in the engine torque indication, with a corresponding drop in the engine oil pressure indication. The pilot diverted to the nearest airstrip, which was Beagle Bay, WA. The pilot shut the engine down when the low oil pressure warning light illuminated and conducted a landing at Beagle Bay airstrip. The aircraft overran the airstrip, coming to rest upside down after impacting a mound of dirt. The aircraft was seriously damaged. The pilot, who was the only occupant, sustained minor injuries.]
There was also another Caravan accident in PNG, where the engine failed and the pilot done a really good job of getting the aircraft onto a short grass runway and the aircraft overrun the airstrip and ended up in a river. I think the aircraft was P2-SAH, the report is on the PNG AIC website I believe.
Sadly there was a fatality due to the evacuation in the river, however the pilot done an executional job getting the aircraft onto an airstrip, given where he was at the time the engine failed.
Ps, Zac I think the accident you are referring to happened at Broome - I maybe incorrect.
Sadly there was a fatality due to the evacuation in the river, however the pilot done an executional job getting the aircraft onto an airstrip, given where he was at the time the engine failed.
Ps, Zac I think the accident you are referring to happened at Broome - I maybe incorrect.
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Well said, as it turns out I was the PIC.
Still no word on why the Allison 250 B17 failed, but all the normal stuff has been ruled out, we just copped the one in a million and a bit hours lottery.
Your comments were spot on, the only thing to add was that there was a R44 working on the field that provided wind info dictating the change to 18, but we couldn’t sight it on first pass so decided we had enough height to go around again.
Your comment about sink rate over the river makes a lot of sense given what happened.
We arrived overhead on first pass at almost 9000ft, a little too high to slip in.
After a complete circuit where we could not see the R44 who had reported being on 18, we started a left downwind for 18 at a little over 1500ft. Unfortunately, on the base turn the wind was far more gusty down low and significantly reduced our ground speed, so by the time we turned final, the choice was Flaps up and increase speed to try and make 18, or go as slow as possible without stalling to put her in with the least amount of energy.
I chose the latter, and my passenger walked away, and I got off easy with some broken bones.
After reviewing the flight logs, I probably should have told the local traffic to bugger off and put her down on 18 on the first circuit, but hindsight only works after the event, and I will happily take the final result any day of the week.
ATC, the Australian Army and the emergency services could not have been more helpful, and thanks to the docs at Canberra hospital for putting Humpty Dumpty back together again.
Still no word on why the Allison 250 B17 failed, but all the normal stuff has been ruled out, we just copped the one in a million and a bit hours lottery.
Your comments were spot on, the only thing to add was that there was a R44 working on the field that provided wind info dictating the change to 18, but we couldn’t sight it on first pass so decided we had enough height to go around again.
Your comment about sink rate over the river makes a lot of sense given what happened.
We arrived overhead on first pass at almost 9000ft, a little too high to slip in.
After a complete circuit where we could not see the R44 who had reported being on 18, we started a left downwind for 18 at a little over 1500ft. Unfortunately, on the base turn the wind was far more gusty down low and significantly reduced our ground speed, so by the time we turned final, the choice was Flaps up and increase speed to try and make 18, or go as slow as possible without stalling to put her in with the least amount of energy.
I chose the latter, and my passenger walked away, and I got off easy with some broken bones.
After reviewing the flight logs, I probably should have told the local traffic to bugger off and put her down on 18 on the first circuit, but hindsight only works after the event, and I will happily take the final result any day of the week.
ATC, the Australian Army and the emergency services could not have been more helpful, and thanks to the docs at Canberra hospital for putting Humpty Dumpty back together again.
