Gulfstream concedes flaw
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Terrible design.
Boeing Aircraft do not have gust locks.
No need as control surfaces are damped with hydraulic power on and snubbed with power off.
Can't understand why Gulfstream couldn't do the same thing.
Boeing Aircraft do not have gust locks.
No need as control surfaces are damped with hydraulic power on and snubbed with power off.
Can't understand why Gulfstream couldn't do the same thing.
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The old HS748 turboprop has gust locks as well with a similar sort of protection system preventing the throttles from being moved forward simultaneously beyond a certain amount to be used for taxiing(one throttle alone could be moved forward for an engine run).
Apparently there was a case where the lock engaged on the takeoff roll leading to a crash with at least one resulting change being that the pilot had to move the control column back and forth a bit during the takeoff roll to ensure that the elevator was still free. Lack of freedom meant an RTO.
Aside from properly following the checklist, it may not be a bad idea to do this kind of elevator check on any aircraft with gust locks just in case you happened to have some sort of failure as well. Might have alerted this crew to a problem early in the roll.
A higher risk scenario might be in a training scenario where you landed, put locks on, backtracked, takeoff again and forgot to remove the locks combined with these two examples of mechanical protection failure.
Apparently there was a case where the lock engaged on the takeoff roll leading to a crash with at least one resulting change being that the pilot had to move the control column back and forth a bit during the takeoff roll to ensure that the elevator was still free. Lack of freedom meant an RTO.
Aside from properly following the checklist, it may not be a bad idea to do this kind of elevator check on any aircraft with gust locks just in case you happened to have some sort of failure as well. Might have alerted this crew to a problem early in the roll.
A higher risk scenario might be in a training scenario where you landed, put locks on, backtracked, takeoff again and forgot to remove the locks combined with these two examples of mechanical protection failure.
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True. And a good example of why not to rely on warning systems to save the day. Just like the Delta 727 in DFW and Northwest MD-80 in DTW where the flaps were left up and the configuration warning failed to provide a warning.
Have to triple check certain killer items yourself perhaps outside of the checklist.
Have to triple check certain killer items yourself perhaps outside of the checklist.
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Perhaps go backwards to a large red "remove before flight" flag attached to a "key" that operates the gust locks externally Then that same "key" could be designed to release throttle-locks IE it must be inserted and locked in place before throttles could be moved from closed. ?....yep, a ballache, but it would save stupid from itself. )(apart from the danger that some smartass would use a duplicate "key" to unlock the throttles whilst the controls were still locked.
make it idiot-proof, you'll breed a better class of idiot.
These people were killed by complacency.
make it idiot-proof, you'll breed a better class of idiot.
These people were killed by complacency.
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How hard is it to do a control movement and freedom check prior to taking off? Is it really unreasonable to expect a pair of professional aviators to do so prior to taking off?
I'm just an uneducated SLF, but it seems to me that the problem here was the pilots, not the plane. If they had done the control system check, they would have found that the gust lock was still on.
I'm just an uneducated SLF, but it seems to me that the problem here was the pilots, not the plane. If they had done the control system check, they would have found that the gust lock was still on.
True, OLFSLF, but not doing to checks didn't cause the accident, the gust lock being place did. It's a fine line, but the design caused the accident, the pilots contributed by their negligence and could have averted the outcome by performing the checks.
GF
GF
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All Gulfstream models prior to the G650 utilized a gust lock mechanism, which from personal experience I can say never once presented a problem. It was always very straight forward, follow the checklist; release the gust lock prior to engine start and do the full flight control checks (Which take all of about 5 - 10 seconds) after engine start.
If you read the full transcript of the NTSB report as well as Gulfstream's report on the testing of it's gust lock system you will see numerous references to the handle mechanism being "worn" or "broken". (Physical evidence from the accident airplane shows that the handle was not in the fully down position and the handles that failed to fully protect in the Gulfstream tests were similarly worn.)
I'd say that Gulfstream is not so much conceding that the mechanism is defective, rather they are giving crews a stern warning, follow the procedures in the AFM and checklists.
Gulfstream's newest model, the G650 doesn't use a gust lock and instead relies on hydraulic damping to prevent control surface damage. Interestingly, years of habit of following the "Before engine start" checklist of the previous models still occasionally causes me to reflexively say "Gust-lock, released".
If you read the full transcript of the NTSB report as well as Gulfstream's report on the testing of it's gust lock system you will see numerous references to the handle mechanism being "worn" or "broken". (Physical evidence from the accident airplane shows that the handle was not in the fully down position and the handles that failed to fully protect in the Gulfstream tests were similarly worn.)
I'd say that Gulfstream is not so much conceding that the mechanism is defective, rather they are giving crews a stern warning, follow the procedures in the AFM and checklists.
Gulfstream's newest model, the G650 doesn't use a gust lock and instead relies on hydraulic damping to prevent control surface damage. Interestingly, years of habit of following the "Before engine start" checklist of the previous models still occasionally causes me to reflexively say "Gust-lock, released".
'Gulfstream's newest model, the G650 doesn't use a gust lock and instead relies on hydraulic damping to prevent control surface damage'
This is what is standard on transport category aircraft, gust locks are asking for trouble, time to get rid of them !
This is what is standard on transport category aircraft, gust locks are asking for trouble, time to get rid of them !
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True, OLFSLF, but not doing to checks didn't cause the accident, the gust lock being place did. It's a fine line, but the design caused the accident, the pilots contributed by their negligence and could have averted the outcome by performing the checks.
