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I found this instagram video via YouTube:

YouTube screenshot

The description in the YouTube video states that:

This aerodynamic baking procedure is applied to reduce wheel brake and engine wear

I have two questions:

  1. Is this a normal procedure for the 747? If so, does anyone have an excerpt from the pilot manual for this?
  2. How would this reduce engine wear? As you can hear in the audio of the video, the thrust reversers seem to be applied the same.
nodapic
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    Since that plane's body in white with no (visible) tail number, it may be testing. With no main deck windows, it's definitely a freighter. – FreeMan Sep 20 '21 at 17:59
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    Oh, the nose wheel is still in the air. So the pilot keeps applying elevator during the whole landing. Was wondering what this “aerodynamic braking procedure” was supposed to be. Hard to see the nose wheel in the shot. – Michael Sep 21 '21 at 05:29
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    Aerodynamic braking is not a normal or effective procedure in air carrier or corporate/business jets. Land on the main gear, fly the nose wheel to the runway and apply brakes and reversers as necessary. –  Sep 21 '21 at 22:58
  • I can think of one, and only one, circumstance in which this would be useful: landing with wheelbrakes completely inoperative. – Vikki Sep 22 '21 at 01:32
  • "Hard to see the nose wheel in the shot" --@Michael. Yeah, real hard! Is the NLG actually down? I don't even see gear doors open. There's a bright spot right about where the NLG should be, but that could be a reflection from the structure behind the plane. – FreeMan Sep 22 '21 at 17:03
  • @FreeMan That bright spot is the taxi or runway turnoff light on the nose gear structure. If you watch the linked YouTube video, you'll clearly see the gear is down. – Bianfable Sep 22 '21 at 17:30
  • I thought it might be a NLG mounted light, but wasn't sure - I thought the landing lights were mounted with the MLG, and didn't know about a taxi/turnoff light. I see the tire, now, but didn't when I was looking a bit ago. Thanks, @Bianfable – FreeMan Sep 22 '21 at 17:35
  • What's "this aerodynamic baking[sic] procedure"? Your question needs to be complete in itself without access to the off-site links. (Context in the answers suggest that it's referring to holding the nose high for some time, but that's not mentioned anywhere in the question). – Toby Speight Sep 23 '21 at 10:25

2 Answers2

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This is not a recommended procedure for landing the 747 (or any other jet airliner I know of). The FCTM (Flight Crew Training Manual) says this:

After main gear touchdown, initiate the landing roll procedure. If the speedbrakes do not extend automatically move the speedbrake lever to the UP position without delay. Fly the nose wheels smoothly onto the runway without delay. Control column movement forward of neutral should not be required. Do not attempt to hold the nose wheels off the runway. Holding the nose up after touchdown for aerodynamic braking is not an effective braking technique and may result in high nose gear sink rates upon brake application.

(Boeing 747-400 FCTM - 6.17 - Landing Roll, emphasis mine)

Bianfable
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    Same warning for A320/A330 + risk of tail strike or hard nose gear touch down when coupled with autobrake. Using this technique may indicate a former military pilot, who used it on fighters due to small brakes. – mins Sep 20 '21 at 17:49
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    @mins Good point about fighters (related question: Is aerodynamic braking really effective?) – Bianfable Sep 20 '21 at 18:04
  • @mins, not sure how accurate this is, but I was once told that you can tell what branch of the military a pilot came from based on how they land. Navy pilots will land tail-down because they were trained to land on aircraft carriers and had to catch an arrester cable with the tail hook. – Seth R Sep 21 '21 at 15:14
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    @SethR All planes land tail-down, though. Find me a pilot who puts the nosegear down first! The big difference with carrier landings is that you hit the deck at like -700fpm, and that's a habit that doesn't really carry over well to heavy airliners. – J... Sep 21 '21 at 16:14
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    The high nose gear sink rates is perhaps a polite way of saying "now that you've finally stalled both the wings and the tail, anything that was up in the air will just slam into the runway as-if in freefall but if you brake, it'll do it even faster than that". The brake application is what you do to achieve said stall first, and second it generates an additional "slam torque" :) It's very much an uncontrolled situation at this point, since controls are ineffective. – Kuba hasn't forgotten Monica Sep 21 '21 at 17:08
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    @J...: "Find me a pilot who puts the nosegear down first!" Here ya go. – Vikki Sep 22 '21 at 01:26
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    @Vikki Never say never, I guess. That's bonkers. Like trying to land a unicycle. – J... Sep 22 '21 at 01:38
  • @Kubahasn'tforgottenMonica Neither the wings nor tail(plane)/horizontal stabilizer are fully stalled on a normal, properly-executed landing, and if the tailplane was, it would be impossible to hold the nosewheel off the ground. Furthermore, "the brake application is what you do to achieve said stall first" makes no sense at all. – sdenham Sep 22 '21 at 12:23
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To answer question No. 2, such technique would reduce engine wear only in that it would involve applying reverse thrust later in the landing roll and for a shorter time (assuming reverse thrust is disengaged always at the same speed, which is normally in the region of 60 kt), something that the pilot in the video might not have taken full advantage of.

Whether landing a 747 that way is a good idea, is a different matter, and Bianfable's answer quoting from the FCTM provides some indications.

Bonus info: regardless of the wisdom of doing wheelies on landing, the idea of delaying as much as possible the application of wheel brakes and reverse thrust (while dissipating as much kinetic energy as possible through 'free' aerodynamic drag) is sound. The A380, for example, was the first to introduce the Brake To Vacate concept for the autobrake. Unlike the ordinary autobrake settings LO, 2, 3, HI (which are still available and engage wheel braking at constant decelerations as soon as the landing gear is on the ground and the spoilers deployed), BTV starts applying brake pressure just in time to bring the aircraft to taxiing speed when it reaches the selected runway turn-off, not before.

Deeday-UK
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