UPS DC-8 in the mud @ GSO

[erichartmann]

The rudder pedal control of the nosewheel is the only steering function affected by groundshift to the flight mode. The tiller still works until hydraulics are removed during retraction, and you can turn the nosewheel in flight with the gear down using the tiller (it's the first thing to try to raise the gear if you have trouble raising the gear). I'm with kaveman on our power application policy, and with heavyjet on being aligned with the runway when setting takeoff power at light weight and with an aft CG is a very good thing to do! (not saying the UPS crew wasn't...)

As I recall the extention of the nose strut engages the centering cam for the nose gear (which effectively disables the tiller) and puts the a/c in the "air" mode both electically and mechanically. Among other things it allows the gear to be retracted without pushing the "override" button. Turning the tiller if the gear handle cannot be moved before pressing the override button is an effort to dislodge the nose strut if it is not fully extended and allows the gear to be retracted normally.

 

[b707guy]

There's a valve that's mechanically operated by the physical extension of the nose wheel strut through the ground shift mechanism that shuts off the direct supply of system pressure to the steering, but as long as the gear itself is down, the same pressure that keeps the nose gear down is also supplied to the steering control valve. All the centering cam does is center the nose wheel when the strut is fully extended, and has no effect on hydraulics or ability to turn the nose wheel. First beer's on me if I'm wrong (and I may be!). You're right about moving the tiller if you can't raise the gear handle, which, if for some reason the strut didn't fully extend after liftoff may allow full extension and release the anti-retract latch.

 

[erichartmann]

There's a valve that's mechanically operated by the physical extension of the nose wheel strut through the ground shift mechanism that shuts off the direct supply of system pressure to the steering, but as long as the gear itself is down, the same pressure that keeps the nose gear down is also supplied to the steering control valve. All the centering cam does is center the nose wheel when the strut is fully extended, and has no effect on hydraulics or ability to turn the nose wheel. First beer's on me if I'm wrong (and I may be!). You're right about moving the tiller if you can't raise the gear handle, which, if for some reason the strut didn't fully extend after liftoff may allow full extension and release the anti-retract latch.

I too could be wrong. It's been the better part of 10 yrs since I left the -8 for a more civilized ride, and I didn't take the time to dig the old manuals out of the basement and review the system. :laugh:

 

[hvydriver]

I too could be wrong. It's been the better part of 10 yrs since I left the -8 for a more civilized ride, and I didn't take the time to dig the old manuals out of the basement and review the system. :laugh:

707 guy is right.

 

[b707guy]

...and I didn't take the time to dig the old manuals out of the basement and review the system. :laugh:

OK, just don't pay attention to the other things I do in my basement:nuts::laugh:

It's probably all moot anyway. Just anxious to see what happened so it doesn't happen to any of the rest of us some day!

 

[erichartmann]

OK, just don't pay attention to the other things I do in my basement:nuts::laugh:

Heaven forfend!!! I have no desire at all to tread into TMI territory.:blush: :0 :beer:

It's probably all moot anyway. Just anxious to see what happened so it doesn't happen to any of the rest of us some day!

Amen!!!

 

[kaveman9]

Moot indeed, as the tiller was working. I think we all agree that you can't stomp the brakes hard enough to skid the nose,...............although I'm sure they were trying.

I just hope they didn't dick up the plane too bad. It pains me to see another -8 gone. I got to land in Philly a few years back while an OOPS DC-8 was smoldering on the runway. Ya know,...............they ain't makin any more of them.

 

[b707guy]

Yeah, it was already leaving marks at what appears to be just past the 1000 foot markers (I know, they're just out of view in the picture) and way off the centerline, but I don't know offhand if there's a displaced threshold there for them to have built up a head of steam farther back. Sure happened quick either way. Waitaminnit - our folks didn't pull an old-style Kalitta and "borrow/trade" some nosewheel components from UPS at PDX to get ours fixed, did they?

 

[hvydriver]

Moot indeed, as the tiller was working. I think we all agree that you can't stomp the brakes hard enough to skid the nose,...............although I'm sure they were trying.

I just hope they didn't dick up the plane too bad. It pains me to see another -8 gone. I got to land in Philly a few years back while an OOPS DC-8 was smoldering on the runway. Ya know,...............they ain't makin any more of them.

Speaking of UPS, talked to two buddies of mine over there. (One a maint. suit, the other a line dog) They both confirmed that they are still planning on scrapping the Diesels over there as they remove them from line service. That is I believe over 40 Diesels. Oh well.

 

[b707guy]

And, I believe, they (UPS) own all the STCs for our beloved Douglas beauties. If so, then once they stop flying theirs, the rest of us are SOL for support. How many does Astar have now? APC shows only 8.