767 Landing Gear
- Thread starter Diamnd15
- Start date
B767Driver
New Member
Diamnd15 said:
There is no reference in any manual of mine that addresses this. I suppose they figure this is not important information for pilots to know.
At one point in time, aircraft manuals contained lots and lots of schematics and peripheral information. Not anymore. Now they pretty much just tell you what to do when a light comes on.
I remember on the 727 you used to have to use some knowledge to determine if a bleed air leak was on the engine or cabin side of the engine pylon...and then isolate the leak.
Newer generation airplanes just turn off the bleed valve and tell you about it.
Minnesota_Flyer
New Member
Nice that the plane keeps you in the loop.B767Driver said:
BPF
Well-Known Member
Similar question for the heavy jet guys...
I know that some of the main gear on jets is just "fixed" (doesn't droop-717 for example) when it comes in for landing, but on heavier jets the gear droops down and contacts the runway earlier. This I imagine serves the purpose of spinning the wheels up before all the weight is transferred to the wheels. Now, is it to aid in a smoother touchdown, reduce tire wear, both, or something else??
Thanks
I know that some of the main gear on jets is just "fixed" (doesn't droop-717 for example) when it comes in for landing, but on heavier jets the gear droops down and contacts the runway earlier. This I imagine serves the purpose of spinning the wheels up before all the weight is transferred to the wheels. Now, is it to aid in a smoother touchdown, reduce tire wear, both, or something else??
Thanks
B767Driver
New Member
KBUF said:
Someone else will know a more technical description, but I always thought that the trucks tilted to provide a more even distribution of stress on the numerous landing gear during touchdown.
My perception is that the tilt does not provide for a smoother touchdown...but maybe other factors are involved besides the tilt. For example, and not so much so in the 757, but in the 767 when you make a smooth initial touch...it is followed by shuddering and shaking as the nosewheel is lowered to the pavement. I always attributed this to the trucks working level to the pavement. Did not really experience this type of shuddering in non-tilting gear.
The L Train
Well-Known Member
I was told in 767 school was that it was that way becuase of LGA. You can only have so much weight per square foot. The 767 original landing gear design did not fit the limits for the runway, so they madethe main gear wider. If I remember right they tilted each main out by 17 degrees.
seagull
Well-Known Member
LGA does have some unusual requirements, which led to AA's A300s having a unique wider truck design for the same reason. The 767 was likely just designed that way with some of the U.S. carriers being launch customers.
As for smoother touchdown, no, the tilt is just to fit into the well. There are issues with both forward and aft tilt from a design standpoint, as forward tilt can lead to more bogey twist at touchdown with a sideload, but that just requires a stronger structure. The reason bigger airplanes have trucks and not just single tandem sets for MLG is just due to the limits on pavement and also tires and related components. More weight and you add more wheels to distribute it, simple as that.
As for smoother touchdown, no, the tilt is just to fit into the well. There are issues with both forward and aft tilt from a design standpoint, as forward tilt can lead to more bogey twist at touchdown with a sideload, but that just requires a stronger structure. The reason bigger airplanes have trucks and not just single tandem sets for MLG is just due to the limits on pavement and also tires and related components. More weight and you add more wheels to distribute it, simple as that.
B767Driver
New Member
Are we talking LGA as in KLGA? I'm guessing due to the pier construction. If so, interesting that one airport has such an influence on design.
The L Train
Well-Known Member
B767Driver said:
KLGA is the culpret.
Maximilian_Jenius
Super User
KBUF said:
LOL..I think the main reason that the 717 gear doesn't "droop" or "tilt" is because it is a two wheel boggie and not a four wheel design!
Just a heads up..
FlyChicaga
Vintage Restoration
Two wheel gear do tilt on some aircraft. For instance, on our EMB-145 we have "trailing link" landing gear, which is an extendable linkage which allows the landing gear to "extend" in a way. This opposed to the B717/MD-80 style gear which is a straight gear assembly.
If airliners.net wasn't down at the moment, I would post some pictures of the differences.
If airliners.net wasn't down at the moment, I would post some pictures of the differences.
Maximilian_Jenius
Super User
FlyChicaga said:
If it is anything like the mains on the CRJ Matt I know what your talking about. There straight when airborne but "tilt" upon impact with the ground..right? When A.Net comes back up could you post a pic please?
FlyChicaga
Vintage Restoration
Just like the CRJ. Many aircraft have that trailing link type landing gear. Airliners.net is still all messed up. Man, I think if Flightinfo.com and Airliners.net combined you'd see an explosion of rude, know it alls who flame, infest the internet message boards overnight.
