Ratypus
Topic Author
Posts: 185
Joined: Thu Apr 15, 2004 8:26 pm

Landing A Jet

Thu Oct 21, 2004 12:53 am

Going out to airline pilots, or simply anyone who knows any more than I do!!

My question is - How do you land a jet aeroplane?

The background to this question is that I've recently started playing Flight Sim 2004 and am taking the lessons. I'm pretty confident flying the Cessna now, landings included.....but before I take any serious jet lessons....what's different?

Main things I'm not sure about - how far out from the threshold would you "normally" expect to be lined up with the runway? What's a appropriate descent rate? What sort of airspeed are you trying to maintain on the glideslope?

Before you say it - I know all this will vary hugely depending on airport/aircraft/ATC patterns etc etc.....what I'm looking for is a run-down of what a pilot is actually doing when he/she brings the plane into land. Flaps - yes or no? etc....Any answers much appreciated - I've never quite worked it out on the flights I've been on!!

P.S except landing in La Paz, Bolivia....I don't even want to know how they did that! It was fun...
 
SlamClick
Posts: 9576
Joined: Sun Nov 23, 2003 7:09 am

RE: Landing A Jet

Thu Oct 21, 2004 2:12 am

Some generalities about landing swept-wing jets.

Consistently decent landings ("good" landings are subject to some differences in definition) begin with a stablized approach. Ideally this would mean that we were aligned with the runway centerline and on the 3o glideslope at the final approach fix, which is usually five or six nautical miles out.

The realities of traffic management at busy airports means that they will often ask us to maintain "at least 180 to the marker" or similar request. Where our landing ref speed might be around 140 or so, this might mean that we would (in the real world) cross the FAF with gear down and flaps at about the second notch, maybe 15 for a 737 and 2 for an A-320. These are approximates of course. Reaching the FAF we would immediately begin extending the flaps to the final setting and in any event the last three or four miles, the last 900' to 1200' of descent would be made fully configured.

If you sat on the jumpseat for this phase you might think it was all locked down and stabilized, but the atmosphere is a turbulent place. In older, more manual airplanes, like a DC-9 the pilot flying is truly flying. He is constantly making tiny corrections to deviations you might not have even seen. Pitch and roll to follow the localizer and glideslope, peeks out the window to confirm a three degree approach to the aiming markers. Almost constant minor adjustments of power to maintain proper speed and glideslope tracking.

When we get down into the runway environment, say crossing the threshhold at fifty feet (a 3o glideslope is a 1-in-20 descent so 50' at the first brick of the runway and you touch down 1000' down - on the markers) it is more eyeballs out the window. This is the region of skill and finesse. We typically will look well down the runway and not up close to the plane. This gives us a sense of our speed, drift, height above touchdown and attitude.

There are several events which make up a landing. Where they occur depends on the type of aircraft. I will run through them in order.

  • Begin the flare. This is often just a slight increase in pitch attitude, a degree or two to slow the descent. In smaller jets it may be down around twenty feet or so wheel height, or radar altitude. In a large jet it may be a hundred or so. This slows the descent, places the plane in a proper attitude for touchdown and begins consuming the excess energy.

  • Thrust reduction. This may be a gentle squeezing-off of the power to a simple placing the Airbus thrust switches in the OFF position, so to speak. Down final we may have been carrying something on the order of 70% or so. We will pull it off to flight idle. On touchdown it will drop to ground idle.

  • Touchdown. In the absence of a crosswind, it is just a matter of letting the increased pitch attitude and the idling engines bleed off the energy until, ideally, you run out of energy just as the wheels touch down, AT the aiming markers. Firm is good on a wet runway, smoothly if your ego demands it, but it is more important that the touchdown take place ON-Speed and in the right place than that it be smooth.

  • Begin braking. Brake commensurate with how many feet of runway lie between your touchdown point and the taxiway you are going to exit on. Reverse thrust early. With carbon brakes, heat them up early. If you are rolling to the far end of a twelve mile runway, let it roll. Good technique here is to take a quick look to confirm ground spoiler deployment.

  • Lower the nose to the runway. At some point the nosewheel steering will become more important than the rudder authority. It is a good thing to have the nosewheels on the ground when this happens. When it happens is a secret.


  • If you are going to be flying jet airliners, I'd recommend reading "Fly the Wing" by Jim Webb (ISU Press, ISBN # 0-8138-0545-7) It is still as good as anything I've ever read on the subject. My compliments to Captain Webb! I often see it in used book stores at considerable savings.

    Hope that barrage helps.
    Happiness is not seeing another trite Ste. Maarten photo all week long.
     
    Ratypus
    Topic Author
    Posts: 185
    Joined: Thu Apr 15, 2004 8:26 pm

    RE: Landing A Jet

    Thu Oct 21, 2004 6:52 am

    Thanks very much - going to read through this again and take it in! Thanks for putting in so much detail
     
    kc7mmi
    Posts: 834
    Joined: Sun Oct 19, 2003 3:15 am

    RE: Landing A Jet

    Thu Oct 21, 2004 7:40 am

    Man, I have no idea what y'all just said! Landing helicopters is so much easier!  Laugh out loud Good luck Ratypus.
     
    User avatar
    Starlionblue
    Posts: 17085
    Joined: Fri Feb 27, 2004 9:54 pm

    RE: Landing A Jet

    Thu Oct 21, 2004 8:05 am

    Good technique here is to take a quick look to confirm ground spoiler deployment.

    Stupid question maybe: Through the window or at the actual lever?


    Lower the nose to the runway. At some point the nosewheel steering will become more important than the rudder authority. It is a good thing to have the nosewheels on the ground when this happens.When it happens is a secret.

    When you feel the bump?  Smile/happy/getting dizzy


    Man, I have no idea what y'all just said! Landing helicopters is so much easier!

    Helicopters don't fly. They're so ugly the ground repels them  Big grin This is of course with the exception of the Agusta A109, which is truly a beautiful flying machine.
    "There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
     
    SlamClick
    Posts: 9576
    Joined: Sun Nov 23, 2003 7:09 am

    RE: Landing A Jet

    Thu Oct 21, 2004 9:18 am

    "Landing helicopters is so much easier!"

    Maybe eventually.

    In my initial checkout, with maybe ten hours or so, solo in the Bell H-13 I brought one back to Shell AHP in a gusty wind and could not buy a landing in it. I'd approach to a pad, then hover up a lane to our spot, then sideways between two other H-13s. I was okay with setting down out in the lane, but when I got between the two other helicopters I was wiping out the cockpit with the cyclic. A couple of times I decided to shut down out in the lane and go get my instructor. Incredibly frustrating, and anyone who tells you that anything in a helicopter is "easy" is being modest or bragging - not sure which.

    "When you feel the bump? " Actually, you will feel that, but what I meant was secret is the moment when control is transferred.

    Check the ground spoiler activation either by handle movement, or some cockpit indication. Shows on the ECAM in the Airbus. Lots of jets you can see the wingtips but actually being able to see spoiler panels is not likely, they are pretty far inboard.

    Happiness is not seeing another trite Ste. Maarten photo all week long.
     
    nudelhirsch
    Posts: 1371
    Joined: Sun Oct 12, 2003 6:20 am

    RE: Landing A Jet

    Thu Oct 21, 2004 1:34 pm

    I am a Landmark Captian too... Big grin

    Do you ...
    Push down the nose or will it come down?
    When do you apply the brakes, before or after nose is down?
    Same for R/T?

    My FS landings are pretty decent after some training, but I am not sure if it is done like that in the real game too...

    And just for fun, because I did it in FS, do you do touch-and-gos with jets during training? Or full landings?

    Putana da Seatbeltz!
     
    sccutler
    Posts: 5567
    Joined: Thu Jan 27, 2000 12:16 pm

    RE: Landing A Jet

    Thu Oct 21, 2004 2:37 pm

    I had the opportunity to log a couple of hours in a 737-300 sim, biggest surprise for me was how much power one has to carry through the approach- and how long it takes for added power to spool up if needed.

    Managed not to crash anything, enjoyed the experience.
    ...three miles from BRONS, clear for the ILS one five approach...
     
    SlamClick
    Posts: 9576
    Joined: Sun Nov 23, 2003 7:09 am

    RE: Landing A Jet

    Fri Oct 22, 2004 9:32 am

    Well I will try this again. I typed for half an hour only to get a "page unavailable" twice this morning. If I had any sense I'd type the text in Notepad and paste it here when it is working. Anyway . . .

    Nudelhirsh to answer your question I will try to stay in sequence. On mainwheel touchdown, the ground spoilers should deploy automatically. The pilot will pull the thrust levers all the way back if they're not already there, then up into reverse thrust while simultaneously applying wheel brakes.

    At any time after this the pilot will begin to lower the nose to the runway, and that is about how it is. It is not necessary to "push" it down because the center of gravity is always just forward of the main wheels. (If it were aft the plane would fall on its tail. If it was well forward there would not be enough elevator authority to rotate.) So we just sort of let it down.

    On planes without reverse thrust, or with inadequate brakes, you can keep the nose in the air for "aerodynamic braking" which was typical of the older fighters. As an F-4 pilot friend of mine once said: "picture landing a DC-9 with Metroliner brakes." The big thing is, though, with paying passengers in the back end you don't want to hold the nose off until it falls the last ten feet to the concrete.

    In airline training, in full-motion, full-visual simulators we normally do only full stop on those rare occasions when we actually get to land. After the first or second session landings are usually with an emergency anyway. Over a lengthy career I got to do touch-and-goes in a jet airliner on a couple of occasions. Once on a small-town airport in a half-million pound plane whose wings hung far beyond the edge of the runway. Some guy in a Bonanza was taxiing out to take off and he just shut down in the runup area and watched our 16 touch and goes. I got eight, four day and four night. It was one of the all-time big grin days of my life!

    Happiness is not seeing another trite Ste. Maarten photo all week long.
     
    futureuapilot
    Posts: 1329
    Joined: Mon May 24, 2004 7:50 am

    RE: Landing A Jet

    Fri Oct 22, 2004 11:24 am

    All i know is durring approach, the engines are never set to idle, they are set to at least 40% so they can spool up quick. That's all i know!
    -future Big grin
    The Pilot is the highest form of life on Earth!
     
    ZKSUJ
    Posts: 6808
    Joined: Tue May 18, 2004 5:15 pm

    RE: Landing A Jet

    Fri Oct 22, 2004 12:13 pm

    I agree with FutureUApilot about the FS landings.
    I hope this does not turn into a "I play FS so I can do the real thing" thread. It is very disrespectful to the real pilots.
     
    kcrwflyer
    Posts: 2534
    Joined: Tue May 18, 2004 11:57 am

    RE: Landing A Jet

    Fri Oct 22, 2004 12:21 pm

    well on flightsim i usually like to be lined up about 2 miles out, i bring em in at a high landingn speed only using about 25-30 flaps instead of 35+. When you go to flare, make it very shallow or else you will takeoff again. While flaring, about 10 feet above ground, cut power and keep the flare as not to let the bottom fall out. Then set her down real smoothe and stop however you want. Thats reverse for me.
     
    ZKSUJ
    Posts: 6808
    Joined: Tue May 18, 2004 5:15 pm

    RE: Landing A Jet

    Fri Oct 22, 2004 12:25 pm

    I avoid taking off again by full flaps at about 140-150KIAS on a 744. You can flare and it will slow down rather than speed up. But don't flare too soon !!!
     
    kcrwflyer
    Posts: 2534
    Joined: Tue May 18, 2004 11:57 am

    RE: Landing A Jet

    Fri Oct 22, 2004 12:26 pm

    oops, that was pointless. I didnt notice we had a pro up there.
     
    AGrayson514
    Posts: 385
    Joined: Mon May 17, 2004 3:14 am

    RE: Landing A Jet

    Fri Oct 22, 2004 12:50 pm

    You might consider doing a few of the lessons that they have on Flight Simulator...while they can seem tedious at first, they are really a lot of fun, and are extremely helpful. There is also a lot of information available in the groundschool as well.

    Happy Landings!

    ~ Andrew Grayson
    Give a little bit...

    Who is online

    Users browsing this forum: No registered users and 17 guests