seven fatalities at KBED

Lindberg said:
Those are interesting. It's always been under the impression that stuff like that around runways was designed to break away.

This is truly tragic.
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They did. As designed. Notice they are missing at ground level, likely sheared off at the breakaway point.


But when the fuel tanks are separated from the atmosphere by a few layers of sheet metal it doesn't take a lot to breach them.. They took a lot of fuel with them to the crash scene.
 
bnt83 said:
I've always tried to devise a plan before I take the runway. Just say to yourself "what if this doesn't go well" as you advance the throttle to full power.
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That's what V1 is for, a concept that is totally unlike most GA flying.
 
KSCessnaDriver said:
That's what V1 is for, a concept that is totally unlike most GA flying.
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V1 is not a plan of what to do if an engine quits, it's a decision point between two seperate plans. Also, this thread is about a GA airplane.

I initially thought this might be a gust lock issue but then didn't think a GIV would even have a gust lock. If the plane does have one then that's definitely where I'd put my money.
 
If it's gust lock then many missed opportunities. Checklist verification, controls free and clear verification, stall warning verification (which requires yokes to be pulled full aft), etc. Sad. I hope it was not something so simple and preventable for the pilots' families' sake, not that it makes any difference for the victims.
 
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The way the system is apparently designed, I can see how the gust lock could have been missed, but what is interesting is that the TRs appear to be stowed in the wreckage. Might explain the 2500' of skid marks.
 
The gust lock on Gulfstreams is only supposed to be engaged after all hydraulic systems are shut down and pressure is at zero. It is a checklist item for the gust lock to be disengaged before engine start.

When the engines are started and hydraulic systems brought online with the gust lock engaged, any movement of the flight controls can easily overcome the gust locks on the control surfaces. The locking mechanism would be damaged and rendered useless. It is highly unlikely the aircraft made it to the runway without any movement of the flight control surfaces.

The thrust reversers are activated by hydraulic pressure and do not have mechanisms to hold them open. It is quite possible the buckets reverted to the closed position after the hydraulic systems were breached by the crash sequence.

I think it's possible there was a failure of the horizontal stabilizer jackscrew system, which moves the surface according to the flap settings. A failure could have resulted in a control surface incidence which caused the inability of the pilots to rotate the aircraft at takeoff.
 
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3393RP said:
The thrust reversers are activated by hydraulic pressure and do not have mechanisms to hold them open. It is quite possible the buckets reverted to the closed position after the hydraulic systems were breached by the crash sequence.
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Yes, apparently the NTSB briefing mentioned that TRs were indeed deployed. It was pointed out on another board that the TRs are linked to the squat switches so likely closed when the gear sheared off.
 
3393RP said:
I think it's possible there was a failure of the horizontal stabilizer jackscrew system, which moves the surface according to the flap settings. A failure could have resulted in a control surface incidence which caused the inability of the pilots to rotate the aircraft at takeoff.
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Is there some sort of position mis-compare logic on the Gulfstream that would have alerted the pilots to this? I know such a system exists on the Citation Excel. Not to say such system can't fail, or be intentionally ignored.
 
Check out the C5 at Dover afb with gust lock in place on take off. It became airborne but then........
 
Clearly the plane failed to rotate. The mystery is why.
 
dans2992 said:
It's surprising they were still moving fast enough to cause a fatal accident after locking the wheels for 1/2 a mile! Wow!
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Planes have rolled down the runway with the brakes on before:
http://www.telegraph.co.uk/news/wor...pilot-accidentally-turned-on-wheel-brake.html

Yet with a G IVs integrated checklists, I'd think there'd be an obvious non-green checklist item staring at them. Still, all those YouTube videos of planes landing with the gear horn blaring indicates tunnel vision can trump even the most obvious.
 
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Horrible.
 

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Martymccasland said:
Planes have rolled down the runway with the brakes on before:
http://www.telegraph.co.uk/news/wor...pilot-accidentally-turned-on-wheel-brake.html

Yet with a G IVs integrated checklists, I'd think there'd be an obvious non-green checklist item staring at them. Still, all those YouTube videos of planes landing with the gear horn blaring indicates tunnel vision can trump even the most obvious.
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eh? No evidence they had brakes on the whole time. They applied braking after v1 and vr.
 
frcabot said:
Thanks, I know how to google. That had nothing to do with a gust lock. So again, link?
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I'm trying to find it my own sef! It's not the C5 which went down due to crew negligence on engine out. I now think it was a C130, not a C5. I saw this about a year ago and it showed the takeoff and the abrupt climb, a turn to the left I think, then down to just before it hit, when the video ended. It explained that the gust lock was left in place. There's another of a caribou but that's not it.
 
Jimmy cooper said:
I'm trying to find it my own sef! It's not the C5 which went down due to crew negligence on engine out. I now think it was a C130, not a C5. I saw this about a year ago and it showed the takeoff and the abrupt climb, a turn to the left I think, then down to just before it hit, when the video ended. It explained that the gust lock was left in place. There's another of a caribou but that's not it.
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You are thinking of the Caribou accident in canada.
 
It was southern air (CIA) flying a c 130 , in 1986 took off with gust lock in place, made abrupt climb, turned off to the left, inverted , crashed. Happened out west, not at Dover.
 
Hmmmmm..

"The NTSB says that data recovered from the flight data recorder a Gulfstream IV jet that was involved in a fatal runway excursion at Hanscom Field in Bedford, MA Saturday suggests the pilot was trying to stop the airplane after reaching about 190 miles per hour".

That is WAY past rotation speed....:confused:....:confused:...:yes:
 
Wow, what is rotation speed in that aircraft?

I would guess around 120 - 130
 
Strange. So it looks like the gust lock was not engaged, but no record of a control check was found prior to takeoff and during taxi the controls were in a position that matches gust lock engaged.

If the data is correct, they did remove the gust lock but did not do a control check prior to the takeoff roll. Is there a way for the lock to be removed physically but the controls still be "locked?"
 
"Review of FDR data parameters associated with the flight control surface positions did not reveal any movement consistent with a flight control check prior to the commencement of the takeoff roll."


It sounds as though everything was done correctly by the crew except possibly a controls check and that something had failed. A terrible tragedy, I wonder how long they had been on duty that day.
 
It sounds like the gust lock was engaged, even though the lever was in the off position. Earlier in the this thread it was mentioned that the gust lock needs to be disengaged before the engines start and there's hydraulic pressure. Maybe that didn't happen and the hydraulic pressure broke the gust lock mechanism so that moving the lever did nothing.
 
MassPilot said:
.......

Maybe that didn't happen and the hydraulic pressure broke the gust lock mechanism so that moving the lever did nothing.
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If that's the case, then it sounds like the system is an accident waiting to happen.
 
MassPilot said:
It sounds like the gust lock was engaged, even though the lever was in the off position. Earlier in the this thread it was mentioned that the gust lock needs to be disengaged before the engines start and there's hydraulic pressure. Maybe that didn't happen and the hydraulic pressure broke the gust lock mechanism so that moving the lever did nothing.
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Maybe I am not understanding the report, but is sounds as though the physical lock on the elevator was also disengaged. The report says "the elevator gust lock latch was found not engaged." Unless the disengagement occurred during the crash sequence?
 
Timmer said:
Strange. So it looks like the gust lock was not engaged, but no record of a control check was found prior to takeoff and during taxi the controls were in a position that matches gust lock engaged.

If the data is correct, they did remove the gust lock but did not do a control check prior to the takeoff roll. Is there a way for the lock to be removed physically but the controls still be "locked?"
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If so that is a terrible system design.
 
It seems the two pilots were well respected, had high time and were well qualified in this aircraft. Strange situation.
 
Timmer said:
Strange. So it looks like the gust lock was not engaged, but no record of a control check was found prior to takeoff and during taxi the controls were in a position that matches gust lock engaged.

If the data is correct, they did remove the gust lock but did not do a control check prior to the takeoff roll. Is there a way for the lock to be removed physically but the controls still be "locked?"
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It is my understanding that, on that aircraft, the pilot cannot advance the throttle with the gust lock engaged.
 
Bob Noel said:
It is my understanding that, on that aircraft, the pilot cannot advance the throttle with the gust lock engaged.
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True, but the gust lock lever was in the off position even though "the FDR data revealed the elevator control surface position during the taxi and takeoff was consistent with its position if the gust lock was engaged."

Sounds to me like the mechanism was broken.
 
MassPilot said:
True, but the gust lock lever was in the off position even though "the FDR data revealed the elevator control surface position during the taxi and takeoff was consistent with its position if the gust lock was engaged."

Sounds to me like the mechanism was broken.
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Yes. The problem with the prelim is that there are apparently several parts to the gust lock system and it seems a little unclear what exactly they are referring to when they say "the elevator gust lock latch was found not engaged." As I understand it, there is a handle next the throttle quadrant to release the gust lock. That handle will release the throttle lock and also release the pawls that physically lock the controls in place. When the NTSB says "elevator gust lock latch" I am not sure if they are referring to the pawls or the throttle interconnect.

As it was explained to me, if they start engines prior to releasing the lock, the hydraulic pressure in the system will prevent the pawls from disengaging but the gust lock handle will release along with the throttle interlock. Someone else in this thread stated that happened, physically moving the yoke would have sheared the pawls, but I do not know enough to confirm or refute that.

Either way, it sure does look like a gust lock issue. I wonder if the CVR captured any of the pre-engine start checklist items. It would be interesting to know the sequence of releasing the gust lock.
 
MassPilot said:
It sounds like the gust lock was engaged, even though the lever was in the off position. Earlier in the this thread it was mentioned that the gust lock needs to be disengaged before the engines start and there's hydraulic pressure. Maybe that didn't happen and the hydraulic pressure broke the gust lock mechanism so that moving the lever did nothing.
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That explanation, if correct, makes sense. Engines started, gust lever moved after start, hydraulic pressure keeps gust lock in place.

If the lever were found in the release position, wouldn't hydraulic pressure have bled off when the engines stopped?

Disclaimer: I know nothing about Gulfstreams.
 
Norman said:
If the lever were found in the release position, wouldn't hydraulic pressure have bled off when the engines stopped?
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That is another theory that is getting tossed about which might explain it if the NTSB is indeed referring to the physical control lock in the prelim.
 
MassPilot said:
It sounds like the gust lock was engaged, even though the lever was in the off position. Earlier in the this thread it was mentioned that the gust lock needs to be disengaged before the engines start and there's hydraulic pressure. Maybe that didn't happen and the hydraulic pressure broke the gust lock mechanism so that moving the lever did nothing.
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'Flyer's,

Sorry...I'm getting in this late and I didn't read all the previous posts, so I apologize in advance if this statement or concept has been covered....

I find it hard to believe that an aircraft manufacturer, such as, Gulfstream would have a gust-lock system (electric, hydraulic, mechanical or any combination) and not have a *fool-proof* feature for disallowing take-off engine power with the system engaged.

For god's sake our spam-cans have a gear horn to keep us from landing with the gear up and that situation is not even life threatening.

I'm positive I'm missing something, so feel free to pile on here.

Gene
 
drgwentzel said:
'Flyer's,

Sorry...I'm getting in this late and I didn't read all the previous posts, so I apologize in advance if this statement or concept has been covered....

I find it hard to believe that an aircraft manufacturer, such as, Gulfstream would have a gust-lock system (electric, hydraulic, mechanical or any combination) and not have a *fool-proof* feature for disallowing take-off engine power with the system engaged.

For god's sake our spam-cans have a gear horn to keep us from landing with the gear up and that situation is not even life threatening.

I'm positive I'm missing something, so feel free to pile on here.

Gene
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And yet people land gear up anyway

Sent from my SCH-I545 using Tapatalk
 
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