Bell 47 crash on video
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hmm. if i can remember my training, 45 mph is the best rate of climb and also best speed for auto's in the 47. the article says that he was at 50' and 45 mph (who knows how accurate that is, though). 50' does not leave you much altitude to establish the auto.
you can hear the pops, but apparently no faults found with the engine. interesting.
you can hear the pops, but apparently no faults found with the engine. interesting.
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The helicopter was damaged when it impacted terrain during an attempted forced landing following a complete loss of engine power. The helicopter had just taken off and was at 50 feet altitude and 45 miles per hour when the pilot heard two loud "bangs" followed by a complete loss of power. The pilot stated that he performed an autorotation to a flat area near the airport. He stated that as he "approached touchdown [he] raised collective to cushion the impact but with so little altitude an autorotation gave very little rotor speed." He stated that the helicopter struck the ground in a level attitude while moving forward, the skids collapsed and the helicopter broke apart. No defects were found with respect to the helicopter's engine.
Why is it that aircraft crashes on video are almost always obscured by trees, other aircraft, crowds or hills?
Were the pops compressor stall? Or was it a case of engine missing...engine found?
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Best rate of climb for a 47 is 39 kts. However you need to climb out at about 45 kts for the first 350 feet to avoid the shaded areas on the height velocity diagram. Assuming he departed into wind the pilot makes an almost 180 degree turn low level. So he would be almost downwind wind the engine stops(if it did stop). So I guess that video is a good demonstration of why we are taught to climb into wind until 500 feet.
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News chopper 4 crash Brooklyn,NY.
Anyone catch the news chopper 4 crash in Brooklyn,NY?
I can't believe all three walked away from that holy
If you haven't caught it you can catch it here.
http://www.unorigial.co.uk/footage40_3.html
I can't believe all three walked away from that holy
If you haven't caught it you can catch it here.
http://www.unorigial.co.uk/footage40_3.html
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TFS
Interesting. The one we used to work off had the velocity curve extended out to above 40 kts. May be different curves for different models of 47. It's still not smart to turn downwind at 50 feet though.
Interesting. The one we used to work off had the velocity curve extended out to above 40 kts. May be different curves for different models of 47. It's still not smart to turn downwind at 50 feet though.
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The theoretical discussions of whether this pilot was inside or outside of the H-V curve are humorous. I guess some of you have no real idea of how fast the rotor rpm goes away when the engine burps for real.
August in Muncie, Indiana, 3:00 in the afternoon. You *know* it had to be hot, whew! Probably little or no wind. The pilot is wearing a helmet. In that heat? Good for him, but oh man I'm sure he had to be fatigued, especially if he'd been in that thing all day long hopping rides.
"That thing" is a G-2, so it should have had good power unless it was sick, which in retrospect it may have been. Nevertheless, it doesn't exactly leap off the ground. The pilot picks up, departs and almost immediately turns 180. He was not much higher than the trees. One loud *pop* later (maybe two), you can actually see the rotor rpm going away and the blades coning. The guy never even put the pitch down. Or flared, evidently, because as he descended behind that tree I could discern no pitch-attitude change and he must've been down to 25 feet by then. All that open farmland and he couldn't do a "simple" straight-ahead auto.
At least, it should have been simple from that altitude: Collective down...flare...level...collective back up. All in about the time it takes to say it. He would have had to accept some run-on in that heat and no-wind condition, but oh well.
I know, I know, "the pilot says" he entered autorotation blah blah blah. I don't buy it. It all happened too fast when he was too low and too slow. We all think that we're going to have the reaction time and precision of Chuck Yeager or Nick Lappos. But the truth is that we normal humans sometimes don't have lightning reflexes. Sometimes it takes half a mo' for things to sink in, but we only have a quarter of a mo' or an eighth of a mo' to do something about them.
Which is why it is good to *not* climb out at 45 mph at 50 feet just because the book says that a sharp-dressed test pilot with a pencil-thin mustache was able to do a planned autorotation from a point on an X-Y graph that was a whole big friggin' 6 mph less. Which is why it is good to not do anything (like make any turns) when you have the collective up by your left pants pocket until you have good altitude and airspeed...and by "good" I mean "sufficiently in excess of the minimums called out in the RFM." Which is why you say to yourself, "The engine is going to quit on THIS takeoff" and you do so because: a) you believe it; and b) one day you'll be right. I have been flying for a long, long time and I still say it prior to every takeoff. Every one.
When you cross that nebulous line between Ops-Normal and Gone-Pearshaped, things start happening very fast. Trouble is, we human pilots don't always anticipate the crossing of that line, nor do we always see it as it speeds past us.
August in Muncie, Indiana, 3:00 in the afternoon. You *know* it had to be hot, whew! Probably little or no wind. The pilot is wearing a helmet. In that heat? Good for him, but oh man I'm sure he had to be fatigued, especially if he'd been in that thing all day long hopping rides.
"That thing" is a G-2, so it should have had good power unless it was sick, which in retrospect it may have been. Nevertheless, it doesn't exactly leap off the ground. The pilot picks up, departs and almost immediately turns 180. He was not much higher than the trees. One loud *pop* later (maybe two), you can actually see the rotor rpm going away and the blades coning. The guy never even put the pitch down. Or flared, evidently, because as he descended behind that tree I could discern no pitch-attitude change and he must've been down to 25 feet by then. All that open farmland and he couldn't do a "simple" straight-ahead auto.
At least, it should have been simple from that altitude: Collective down...flare...level...collective back up. All in about the time it takes to say it. He would have had to accept some run-on in that heat and no-wind condition, but oh well.
I know, I know, "the pilot says" he entered autorotation blah blah blah. I don't buy it. It all happened too fast when he was too low and too slow. We all think that we're going to have the reaction time and precision of Chuck Yeager or Nick Lappos. But the truth is that we normal humans sometimes don't have lightning reflexes. Sometimes it takes half a mo' for things to sink in, but we only have a quarter of a mo' or an eighth of a mo' to do something about them.
Which is why it is good to *not* climb out at 45 mph at 50 feet just because the book says that a sharp-dressed test pilot with a pencil-thin mustache was able to do a planned autorotation from a point on an X-Y graph that was a whole big friggin' 6 mph less. Which is why it is good to not do anything (like make any turns) when you have the collective up by your left pants pocket until you have good altitude and airspeed...and by "good" I mean "sufficiently in excess of the minimums called out in the RFM." Which is why you say to yourself, "The engine is going to quit on THIS takeoff" and you do so because: a) you believe it; and b) one day you'll be right. I have been flying for a long, long time and I still say it prior to every takeoff. Every one.
When you cross that nebulous line between Ops-Normal and Gone-Pearshaped, things start happening very fast. Trouble is, we human pilots don't always anticipate the crossing of that line, nor do we always see it as it speeds past us.
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The guy never even put the pitch down
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PF1
I don't have any argument with your observations or conclusions except to say that I think what you point out makes a discussion of the H/V diagram even more relevant.
Surely if you do a mental run through of an engine failure on every departure partof that discipline would be flying a profile that avoids a combination of speed and height that has been proven to be unsafe ???
I don't have any argument with your observations or conclusions except to say that I think what you point out makes a discussion of the H/V diagram even more relevant.
Surely if you do a mental run through of an engine failure on every departure partof that discipline would be flying a profile that avoids a combination of speed and height that has been proven to be unsafe ???
Overpitched:
Heh- if that were only the case! I did say that I expect the engine to quit on *every* takeoff, but that doesn't mean that I wouldn't sometimes be in a serious bind if it did. Only in a perfect world is every takeoff made over nice, unobstructed, flat areas with lots of places to set it down. Sometimes you just have to grit your teeth, hold your breath and say, "Here we go..." and get into a safe zone as soon as possible.
I am a good pilot- maybe not a great pilot (despite what I may post on silly internet discussion boards). I do not delude myself that I can duplicate all of the techniques that the test pilots demonstrate during certification, even though the graphs and figures and such are supposedly compensated for dimwits such as meself. So I don't get complacent. I don't assume that just because I am *slightly* outside of the shaded area a good autorotation is guaranteed.
It's tempting, when doing repetitive flights, to let things slide a little. With all that open farmland around the airport, one could understand the 47 pilot getting a little complacent. Truth is, he should obviously should have gone for a little more aerospeed than altitude. Or maybe said to himself, "I wonder if it's going to pop and quit on this takeoff?"
I don't have any argument with your observations or conclusions except to say that I think what you point out makes a discussion of the H/V diagram even more relevant.
Surely if you do a mental run through of an engine failure on every departure part of that discipline would be flying a profile that avoids a combination of speed and height that has been proven to be unsafe ???
Surely if you do a mental run through of an engine failure on every departure part of that discipline would be flying a profile that avoids a combination of speed and height that has been proven to be unsafe ???
I am a good pilot- maybe not a great pilot (despite what I may post on silly internet discussion boards). I do not delude myself that I can duplicate all of the techniques that the test pilots demonstrate during certification, even though the graphs and figures and such are supposedly compensated for dimwits such as meself. So I don't get complacent. I don't assume that just because I am *slightly* outside of the shaded area a good autorotation is guaranteed.
It's tempting, when doing repetitive flights, to let things slide a little. With all that open farmland around the airport, one could understand the 47 pilot getting a little complacent. Truth is, he should obviously should have gone for a little more aerospeed than altitude. Or maybe said to himself, "I wonder if it's going to pop and quit on this takeoff?"
