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I don't think that power is still on the rotors there. The spin does stop prior to the crash. That isn't going to happen with power on, and increasing collective near the ground is going to add to the spin. I think this pilot got power off and autorotated it down.
Lucky SOB. Those old Sikorskys were a bit more robust methinks.
The other hazard of keeping power on in a rapid descent is falling into a vortex ring state, which is what might have happened in the G-VSKP crash.
I don't think that power is still on the rotors there. The spin does stop prior to the crash. That isn't going to happen with power on, and increasing collective near the ground is going to add to the spin. I think this pilot got power off and autorotated it down.
Lucky SOB. Those old Sikorskys were a bit more robust methinks.
The other hazard of keeping power on in a rapid descent is falling into a vortex ring state, which is what might have happened in the G-VSKP crash.
Agree, it looks like he laid off very quickly, and still had time to adjust his pitch before he nosed it down. I wonder though if he reapplied power right at the end, because I believe it would still generate lift, and given the relative mass of the fuselage, would take time to introduce enough spin to cause big trouble at that point. Also suspect, the mass of those blades is probably a lot higher on that old Sikorsky than on the newer copter.
I will go on here and speculate that there was more than just a tail rotor fail here. The way that the helicopter starts falling immediately as it starts spinning makes me suspect that there was a problem with the MAIN rotor too. Evan's mention that the incident seems to happen as the pilot start to transition to forward flight makes me think that perhaps the main rotor made contact with the tail rotor.
I think we would have seen some sparks and pieces flying if that was the case. Also, when it takes off, it looks like it is impossible for the two to contact since they pass through the same plane until he lifts off.
My own speculation here is that he did not disconnect the power quickly enough. If I compare the timing of the start of rotation of both videos, is looks like they both laid off the power after a similar number of seconds (hard to tell in the older video because we lose sight), but the newer copter started spinning at a faster rate, I would guess from differences in mass of the copter and torque being applied by the engine. Perhaps even the aerodynamics of the shape even come into play. It looks like that bought the sykorsky pilot more time because his spin was slower at the time of power disconnecting. I understand the drive shaft for the rotor is usually connected to the main rotor gearbox, and I suppose a hardware failure could result in other controls being damaged but based on the time it was hovering after the spin started, and then it quickly descended due to initiation of autorotation (because the spin rate does not seem to increase after the descent starts). I highly suspect the poor pilot was spinning too quickly to properly orient himself to execute the proper cyclic and collective inputs at the right time. He was spinning pretty fast. Of course, we don't see the last actions because the view is obscured, so perhaps they hit something in the parking lot disrupting his attempts to soften the landing.
Not that I actually expect an answer, but where did you learn that?
Evan probably is a guy, who like my two online jetphotos friends, has a life which hasn't to, but can take place offline.. Imho, a very good decision. So, he's not here now.
I sometimes wonder if this forum is only good for jet engines in a/c types such as.. Embraer E190, Embraer E195, Embraer E170.. Somehow, Brazil is on my screen today, I don't know why, officially..
(Interlagos, November 11th, but that would be offtopic.. )
There are guys who I definitely would love as 'my Captain', who I'd trust at once as a jetphotos forum member,
e.g. Helicopter Captain Thilo Kaiser. I know that I've mentioned him here in this forum a few years ago, and I strongly assume that he's able to explain an aircraft like
the jet engined AgustaWestland AW169
for a helicopter nobody like me.
The manufacturer says, this is the first total loss of an AW169 ever. 5 souls on board, all dead. I don't know how much you can learn from TV, if your flight instructor would be Captain Kaiser. Here are the sources which I've used: The AW169 en wiki.
and Mit dem Helikopter durch Afrika, Juni 2010 (in German)
June 2010, by then Captain Kaiser was 51 years old, with a helicopter license since.. 1984. So, as I always say, with an experienced flight captain, no flight should end in a crash.
Btw, isn't that scary, German sources which exist since 2010..
and then we have a look at my join date...
Some people say, a helicopter is the most dangerous aircraft on earth. Completely lost without the second propeller. In contrast to my avatar, or in contrast to an A320.
I assume that I only know pilots who love the life. So, was that fatal accident avoidable, if Captain Kaiser had been on board.
There are two different types of pilots: old pilots, and pilots who don't know what their a/c is good for. Or was the saying
old pilots vs dead pilots.
Kaiser and Sullenberger III are definitely the first type.
So, was it pilot error, with a rather high amount of flight hours total, but a rather very small amount of flight hours on type, AW169?
Something like that is not impossible, I've read about such cases, June 26th 1988, a brand new A320 ..
PS: Another quite brilliant aviation saying, but I only know the German version. But I know that I'm not the only German speakin jetphotos forum member, so, if there is a translation, let's know it:
'Hochmut kommt vor dem Fall!'
Last edited by LH-B744; 2018-11-06, 07:56.
Reason: There are some rather cruel aviation sayings..
The German long haul is alive, 65 years and still kicking.
The Gold Member in the 747 club, 50 years since the first LH 747.
And constantly advanced, 744 and 748 /w upper and lower EICAS.
This is Lohausen International airport speaking, echo delta delta lima.
FWIW- the US headlines are full of a newlywed couple that were killed as they left the wedding reception in a helicopter...commonalities = a whole bunch of moving parts that can fail (despite there being much scientific engineering and low odds).
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
FWIW- the US headlines are full of a newlywed couple that were killed as they left the wedding reception in a helicopter...commonalities = a whole bunch of moving parts that can fail (despite there being much scientific engineering and low odds).
Of course there are a bunch of other parts that can fail. The parts that close the feedback loop when operating a helicopter or a tricycle.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
Some people say, a helicopter is the most dangerous aircraft on earth. Completely lost without the second propeller. In contrast to my avatar, or in contrast to an A320.
I have a friend who has flown his own copter for many years. He's also an engineer and recently got his pilots license. If he needs to go shorter distance, copter is the answer. Med, his plane. Far, commercial jet.
He insists that he thinks the copter is safer. If something goes wrong, you land really fast. He says the mechanics are much simpler, the engine is simple, controls simple. His plane has a lot more complexity.
Under what circumstances and compared to what airplane?
in the case of loss of power, helicopters are most dangerous at low-speed or out-of-ground-effect hover at low altitude. In the case of loss of tail rotor, in a low speed at any altitude.
Twin/multi-engine helicopters are essentially immune to the first danger but not the second (multi-engine pilots often practice autorotation as a loss of altitude, but not all the way to landing). There is no redundancy for tail rotor failure. The only way to regain control is to remove power. But tail rotor failure is very rare these days.
Helicopters with a twin-blade, semi-rigid rotor are vulnerable to mast bumping and, on some designs, tail boom impact.
SInce they conduct landings away from airfields, helicopters are more vulnerable to impact with obstacles, power lines, etc.
Riding in any helicopter with a rigid rotor hub above 60kts forward airspeed at a safe altitude is probably as safe as a conventional airplane, and safer in certain aspects.
If a moving part fails, you are probably more likely to have a flying airplane than a flying helicopter.
As your friend says, if the problem gives you a little time to keep flying (or maybe you hit unexpected IMC), the helicopter is easier (and it's actually pretty legal) to just land in an open spot.
Super duper sophisticated well maintained whatever versus the cheap models...Airliner vs. Junkers, Twin-turbine chopper vs a single reciprocating engine....
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
If a moving part fails, you are probably more likely to have a flying airplane than a flying helicopter.
As your friend says, if the problem gives you a little time to keep flying (or maybe you hit unexpected IMC), the helicopter is easier (and it's actually pretty legal) to just land in an open spot.
Super duper sophisticated well maintained whatever versus the cheap models...Airliner vs. Junkers, Twin-turbine chopper vs a single reciprocating engine....
Totally agree. I was pretty ignorant about it until he walked me through the risks and scenarios. His copter is a small one, single engine, and he does pretty much land it all over.
Well, either they've seen something in the wreckage, they have seen some incorrect maintenance in the past, or they're guessing at the highest likely single failure mode of loss of yaw control.
Well, either they've seen something in the wreckage, they have seen some incorrect maintenance in the past, or they're guessing at the highest likely single failure mode of loss of yaw control.
Four words in the AD sum up the thinking behind it. They are...... “As a precautionary measure”.
If it 'ain't broken........ Don't try to mend it !
Four words in the AD sum up the thinking behind it. They are...... “As a precautionary measure”.
Yeah, that sounds an awful lot like: we think we know what's wrong and better say something now (in case someone else is at risk), but let's not commit yet until we know for sure and we get our lawyers to check everything over.
Yeah, that sounds an awful lot like: we think we know what's wrong and better say something now (in case someone else is at risk), but let's not commit yet until we know for sure and we get our lawyers to check everything over.
Wrong. You can be sure that the lawyers already checked the wording of this AD over.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
The Kobe Bryant crash reminded me to look up the results of this one. Single mechanical failure resulting in loss of control of yaw. Rudder disconnected from the control mechanism.
Investigators found the pilot's pedals became disconnected from the tail rotor and caused the aircraft to make an uncontrollable right turn before it spun and fell, hitting the ground in a ball of flames.
The pedals and tail rotor are linked by a mechanism which failed after parts of it had become disconnected and there was a "build-up of black grease" on one component.
"The tail rotor actuator control shaft became disconnected from the actuator lever mechanism," it added.
"The disconnection stopped the feedback mechanism for the tail rotor actuator from operating and the tail rotor actuator from responding to yaw control inputs."
This loss of the feedback mechanism meant the yaw stops were ineffective and the tail rotor actuator was able to continue changing the pitch of the tail rotor blades "until they reached the physical limit of their travel".
"This resulted in an uncontrollable right yaw."
It went on: "Sufficient force and torque had been applied to the castellated nut on the actuator end of the control shaft to friction weld it to the pin carrier and to shear the installed split pin.
"Whilst the shaft was rotating and a yaw control input was applied, the shaft 'unscrewed' from the nut, disconnecting the shaft from the actuator level mechanism, and causing the nut to become welded to the pin carrier."
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