View Full Version : What is a "gust lock"?
ramsrc
23rd Aug 2004, 06:18
Was reading an article in Septembers "Airliner World" on the way into work this morning about Phoebus Apollo's DC3 out of Johnannesburg.
The article made mention of the necessity of removing the "Gust locks" before the first flight of the day. Hence my question - What is a gust lock?
chiglet
23rd Aug 2004, 07:02
Usually a "physical device" hot unlike a large clothes peg used to stop the control sufaces "flapping" in the wind. More modern a/c have a control clomn lock, I believe. {stands to be corrected]
we aim to please, it keeps the cleaners happy
A gust lock is used to "lock" control surfaces against movement by "gusts".
If they're not removed before first flight of the day, first flight could equal last flight.
The Boy Lard
23rd Aug 2004, 07:09
ramsrc,
I believe its does exactly what it says on the tin!
On the aircraft I fly they are soft circular pads on a long threaded bolt that goes inbetween the edge of the aileron (or other flying control) and the rest of the wing/tail fin.
The idea is that whilst the aircraft is parked the flying control cannot be moved by a gust of wind and damage said surface.
I have also seen some real Heath Robinson contraptions that fit in the cockpit that fit around the yolk and rudder pedals, very difficult to get on and off.
Hope this helps.
TBL
Internal gust locks were very common on older types...DC4's, DC6's DC7's, Stratocruisers, F.27's, etc.
A large cockpit handle was moved to lock the controls in the neutral (usually) position while parked.
Of course, as with any cockpit device, there invariably comes a time when someone wonders...what would happen if I used this in flight?
The crew of a DC4 found out many years ago just west of KELP when a crew member (actually a check pilot in the obs seat) applied the gust lock in flight.
IIRC, the aircraft was unrepairable due to the twist in the wing and horizontal stabilizer.
ramsrc
24th Aug 2004, 05:59
Many thanks for all the replies. Much appreciated - Simple when you know what it is.
Like The Boy Lard said, does exactly what it says on the tin!
sammyhostie3
24th Aug 2004, 06:31
I dont know exactly what it does, but What i do know is that when we have to open the door, we only know its fully open when we hear the gust lock engage. (it clicks)
Similarily when we close the door, we have to depress the gust lock in order to close and "lock" the door.
Hope that helps!
AerocatS2A
24th Aug 2004, 07:40
sammyhostie3, what aicraft type is that on?
Sailor Vee
24th Aug 2004, 09:56
411A,
The old HS748 had internal gust locks, the Dan Air that speared in at Sumburgh was a result of the elevator lock vibrating back to the locked position during the take-off roll, ended up going into the rocks of the breakwater off 09 threshold.
john_tullamarine
24th Aug 2004, 11:33
Likewise, an Australian F27 operator (25 years ago ?) had a gustlock part engage in flight .. causing some considerable flight deck consternation until the penny dropped and the handle was restowed ...
The Fokker F.27 had the gust lock handle just behind the Captains seat, a place I personally thought was hard to reach.
The Fairchild aircraft however, had the gust lock just to the left of the LHS, where it could be more easily reached, IMO.
Engaging in flight...bad idea, for sure.:uhoh: :uhoh:
av8boy
24th Aug 2004, 15:56
http://www2.ntsb.gov/ntsb/GenPDF.asp?id=LAX02FA028&rpt=fi
http://www2.ntsb.gov/ntsb/GenPDF.asp?id=LAX02FA028&rpt=fa
:(
sammyhostie3
25th Aug 2004, 16:28
Aerocat,
On both Boeing and Airbus.
Carnage Matey!
25th Aug 2004, 16:41
The gust locks on the doors stop the doors being blown out of position by the wind.
The old Lockheed C-141 had gust lock check valves installed.
Protected the flight controls when the system was de- pressurized.
Oddly enough, the TriStar had the same...gust lock (control surface protection) while parked.
Lockheed got it right.
Germstone
25th Aug 2004, 21:05
the 748 that overan the runway and took out the ils hut at liverpool some years ago was due to the elevator gust lock engaging..........the 748 fleet worldwide has now been modded to prevent this occuring again
you would have thought after the dan air a/c they would have sorted it years ago
You are correct 411, cannot remember the number on the Tri-Star
but do recall the 70 kts number on the C-141.