United flights with gear down after T/O

matt152

Well-Known Member
I plane spot at BDL (Hartford, CT) frequently.

I have noticed that a couple of United flights have left the gear down for a really long time after takeoff. They make the first turn and are clearly at least a mile from the runway and the gear is still down.

It really sticks in my mind because it is the only time I have ever seen a jet leave the wheels down for so long.

Is there an operational reason for this?
 

Firebird2XC

Well-Known Member
I plane spot at BDL (Hartford, CT) frequently.

I have noticed that a couple of United flights have left the gear down for a really long time after takeoff. They make the first turn and are clearly at least a mile from the runway and the gear is still down.

It really sticks in my mind because it is the only time I have ever seen a jet leave the wheels down for so long.

Is there an operational reason for this?

Some aircraft operations suggest leaving the gear extended a little bit after takeoff. The relative wind helps cool the brakes, which sometimes are still very hot after a short turnaround time on the ground. Letting them get blown cool for a few moments reduces the chance of hot brakes in the event of an immediate return for landing. It also reduces the unlikely but possible chance of a fire breaking out in the gear well.
 

Polar742

All the responsibility none of the authority
One would think that proper procedure would be to raise the gear to ensure 2nd segment performance, then lower the gear once you're out of your acceleration (or level off) altitude.

However, they may have proven via performance programs that at that weight it is acceptable to leave the gear down for the climb out and delay retraction.
 

Firebird2XC

Well-Known Member
One would think that proper procedure would be to raise the gear to ensure 2nd segment performance, then lower the gear once you're out of your acceleration (or level off) altitude.

However, they may have proven via performance programs that at that weight it is acceptable to leave the gear down for the climb out and delay retraction.
Agreed. The 'gear cooling' thing for more than a few seconds doesn't really seem to make alot of sense to me.

I think there may be other reasons, but I'm not going to speculate with this little data. ;)
 
R

Roger, Roger

Guest
That must be the mind control drugs they're using on all of us.
 

rjmore

Gastrointestinally Challenged
I know the ERJ had a couple MEL's that called for leaving the gear down for a minute or two to ensure brake cooling. If I get the motivation I'll see if the -400 has anything similar.
 

rjmore

Gastrointestinally Challenged
Ok, I got the motivation to look it up. I found a few MELs that required the gear to remain down for 2 minutes. I didn't look too much into the rest after that so there may be more. These all had to do with the deactivation or removal of a brake. We have 16 brakes and we can go with 14. The aircraft has a braking feature as the gear retracts to stop the wheels from spinning before they enter the well. Without those two brakes the MEL calls for them to be left down for two minutes to allow the wheels to stop spinning before entering the wheel well.

There may be more but I lost my motivation after I found that one. :D
 

BobDDuck

Island Bus Driver
On the Canadian Law Dart there are a few procedures that call for leaving the gear down, as well as an immediate action item if we get a GEAR BAY OVERHEAT message. I'd have to go look at the MEL book to see if those specific ones say anything about climb performance numbers but I don't remember reading anything about that.
 

granlistillo

Well-Known Member
One day at CLT tower asked a mainline jet if he had gear trouble. He responded he was leaving it down a bit for a MEL.

Would be interesting to see what the performance adjustments were made to ensure 2nd segment performance. Or would you just yank up the gear if you lost one? I certainly would want to know before we went.
 

JLF

Well-Known Member
One day at CLT tower asked a mainline jet if he had gear trouble. He responded he was leaving it down a bit for a MEL.

Would be interesting to see what the performance adjustments were made to ensure 2nd segment performance. Or would you just yank up the gear if you lost one? I certainly would want to know before we went.

This is accounted for where I'm at with just a simple AeroData manipulation.
 

Yank&BankmyRJ145

New Member
One day at CLT tower asked a mainline jet if he had gear trouble. He responded he was leaving it down a bit for a MEL.

Would be interesting to see what the performance adjustments were made to ensure 2nd segment performance. Or would you just yank up the gear if you lost one? I certainly would want to know before we went.
The 2nd segment climb mainly only applies to single engine ops, or unless your airplane is very under powered. With two engines you should not have a problem climbing out with the gear down. If you lost an engine I would hope you would yank the gear up, because thats when your 2nd segment climb starts. Safety first!!!
 

B767Driver

New Member
On the 767ER there is a supplemental hydraulic pump that kicks in to assist with gear retraction. I've had it fail before and it takes 30 to 60 seconds for the gear to begin to retract.

It can be deferred but there is a weight penalty that is pretty severe.
 

rjmore

Gastrointestinally Challenged
I guess the most helpful thing would be to find out what the type was and then get someone currently on it to sniff around their MEL. Anyway, it looks like there are several reasons why it could be done. You'd have to take the weight penalty as mentioned.
 
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