Hello....

I have noticed latly that United Airlines has been extending the landing gear almost way too soon...I understand the importance of getting the gear down to make sure theres no problems, but im speaking in cases of 15-20 miles out from the airfield....I was spotting at Denver these past few warm weekends and United always has gear down at first sight thru Binnoculars, whereas the same A/C type on another airline come down around the marker, as I always remember United doing....

I recently flew into LAX on a UA 752 and the gear was down with only flaps 5 over ONT, about 54 miles east of the runways....Are they doing this to bleed speed or why the sudden change of procedure.....RyRy

This is just speculation, but from listening to air traffic control on my scanner, and from different pilots I've talked to, often ATC will request the pilots to slow to final approach speed, for traffic separation, thus necessitating lowering the gear and flaps... and another thought, might be that it could have something to do with the 757's large wake turbulence? In the dirty configuration it would be less than in the clean configuration.

They lower the gear to help slow the bird down!
Iain

Yes I know it helps slow, but 50 miles out!? And why the sudden shift to this method, and why not other carriers.....RyRy

Hate to tell ya this but ONT is not 54 miles from LAX. ONT is also about where the approach starts and LA controllers are notirous for asking a lot out of pilots.
Iain

Who are you to critizise when they put their gear down anyway? I put mine down when I damn well please, to hell with what people think (as long as I or they are not endangering the airplane or anything else that is).

No offense.  

Ryan,
Not to be critical, but how do you know that they put the gear out?

In the real world, it's up to the discretion of the PF as to when to call for the gear. Typically, it's at the marker or final approach fix "inbound". I can only think of a couple of possible scenarios where a crew would put out the gear so early - 1) If they were having hydraulic issues and they wanted to run the checklists early and get the gear out to avoid being rushed at that stage of the approach. 2) If for some reason the crew suspected that they had snow/ice/slush buildup on the gear, they might consider extending it early to help clear it. As far as using the gear to limit speed, it certainly will do that, but that's what airbrakes are for.

It's more common to delay retracting the gear. A couple of reasons for this would be: 1) In the case where the brake energy limits had been approached the crew might elect to leave the gear down for a little bit for brake cooling. 2) If for some reason the crew suspected that they had snow/ice/slush buildup on the gear, they might consider leaving it out for a bit to help clear it.

My feeling is that you simply mistook some hydraulic noises for the gear being extended. It's a pretty easy thing to do. But hey, I could be wrong, I've never flown a 757 before.

jetguy, i tinhk he said he was spotting (not riding), so idoubt the issue is hearing not seeing. Ralgha- where do you fly out of?

The gear out at 50 some odd miles was when he was flying into LAX

Maybe they did like i did one time when i just started flying complex planes and completely forgot to suck up the gear.  



And the statement of the week is: FINALS BLOW!!!!

Corvallis, OR usually, for the next month or so out of Troutdale.  

Woah! Hey there I wasnt dog'n on the pilot for extending the gear early.....Jetguy your right almost all carriers are gear down around the marker, which i clearly noticed while spotting in Denver.....My flight to LA, and Im sorry if the distance is slightly different lainhol, but still its in excess of 30 miles from LAX....The gear extension on a 757 is very loud, the air in the gear bay is loud and the thump of the gear locking is very evident.....I asked the pilot on exit if the gear was extended at such distance and he advised yes it was and that its just something they have been doing latly, gear then flaps.....No other discussion....Am I being critcal no, am I curious why for years the gear comes down around the marker and now almost all United A/C have gear down very far out....Just curious why United is doing this, perhaps someone can offer some ideas, its obviously a change in United's Tech/Ops....Thanks for the info and sorry if I offended by asking....RyRy

I can tell you that there has been no change in procedure calling for earlier extension of the gear.

As you probably know, most jet aircraft will not decelerate and descend at the same time (At least not very well - the 727 and DC-9 seem to be exceptions). The 757, for example, is so aerodynamically slippery that it's pretty normal to have to use either the speed brakes or the gear to help come down and slow down. For example, say you're coming down on the approach at 230 knots and flaps 1 and DEN approach asks you to slow to 180. Guess what: you're gonna need the drag from the gear to help you slow down while staying on the glide slope profile.


For safety, UA and other airlines fly what's called "stabilized approaches". While each airline uses their own criteria, the concept is to have the aircraft on speed, engines spooled, and in full landing configuration by a certain point on the approach. At United, it's no later than 500' in visual conditions or 1000' in instrument conditions. The gear must be down and final descent checklist complete by the outer marker (instrument conditions) or by 1500' (visual conditions). Not having these things done means a mandatory go-around, and UAL has really been emphasizing the "stabilized approach" lately. The pilot has to work backwards from these numbers to figure out where he should start slowing to make the approach come together by this point, and DEN seems to be a little tricky for a few reasons:

Higher airport elevation means higher groundspeed;

When landing to the south there's sometimes a quartering tailwind pushing you towards the runway, and;

DEN approach usually keeps arriving aircraft high on the way into the airport before cutting you loose on the approach.

For all of these reasons using the gear farther out than normal helps slow the airplane down AND bring the plane down to proper altitude to be stable by the above limits. You could also use the speed brakes in some airplanes, but the gear is usually more effective at dragging the airplane down.

Using the gear early also allows you to keep the speed up longer. The UAL 757 flaps 1 speed is 230 knots, but you can throw the gear out at 270. Rather than start slowing to 230 or so 20 miles out and then feeding in flaps, some pilots like to keep 250 knots until closer to the airport, then drop the gear to drag the aircraft
down to approach speed by the above limits. It's all technique.

Just a few guesses off the top of my head.

61Heavy

One of the arrivals into LAX from the east in the Civet 4 - an arrival with about 5 "step-down" crossing restrictions that feeds straight into the ILS to 25L. I'm guessing this is probably the one you did with the gear down so far out. This arrival involves multiple altitude restrictions and usually changing speed assignments from ATC.

It's a tough one to figure out what configuration and speed will keep you above the crossing restrictions and on speed but still give you time to slow and be stable by the required point on the approach. I haven't flown it in a while but I seem to remember it either requiring the gear WAY early or the speed brakes all the way down.

Bottom line is if the pilot feels he needs to throw the gear out to slow down, he does. it's always better to err on the safe side and be slowed down a little early than to have to go around because you didn't get the airplane in configuration for a stabilized approach.

61Heavy

Thank you so much 61Heavy for the detailed information....The Civet 4 is a tricky one indeed from what I hear, we seemed on the Civet4 however we were not as we change to the northside 24L....I dont have the STARs in front of me, but Im sure the procedures you described are very similar....I have some other questions for you about Denver, would I be able to email you.....Again thank you for your post...Ry

Ry,

It's also not uncommon to be on the Civet4 and have LAX approach change the runway on you at the last second. That one's always fun, too; a lot of last second chart scrambling, typing in the box, and redialing the localizer frequency.  

I'd be happy to help answer any questions you have! My e-mail address is on my profile.

61Heavy