Yoke nose down pressure during rollout

[Hardy Heinlin]

Good evening,

a question for the heavy metal drivers. During a manual rollout, how much do you push the yoke forward, and when do you release the pressure? At circa 60 KIAS perhaps? I guess it depends on the wind. Are there any company specific rules?


Cheers,

|-|ardy

[Mariano]

Hardy,

Our 767 and 747 FCOMs do not mention anything about forward pressure on rollout, nor are we trained to apply any.

During gusty/crosswind landings, sometimes I find myself adding a bit extra nose down pressure, most of which is a subconscious "byproduct" of upwind aileron application (the control wheel deflection tends to make me add a little extra control column forward pressure).

I usually relax the (slight) pressure as the reversers stow.

I am sure that this a topic whose technique varies widely between operators and with personal preference.

Best regards,

Mariano

[double-alpha]

Like Mariano, nothing is mentioned in my 787 FCOM / FCTM

[emerydc8]

Like Mariano mentioned, if there's a crosswind I also like to pin the nose to the runway for extra traction and as the speed bleeds off (probably as reversers are stowed) I relax it.

The 767 has a tendency to "wheelie" a lot more than the 744 when reversers are deployed. If you don't get the nose down at higher airspeeds it becomes a challenge to fly it down without it slamming on while you're deep into reverse. You run out of elevator pretty quickly and I've found myself with the yoke all the way back to prevent the nose from hitting hard. Being a proir DC-8 driver, I have a habit of going into max reverse as soon as the mains touch down (even before getting the nose heading down toward the runway). For some reason, flying the nose down like this is not quite as bad on the winglet aircraft.

Jon

[localiser]

a tendency to "wheelie" a lot more than the 744 when reversers are deployed

Plus 1 for the wheelie comment...

I find the 744 tends to pitch up when the spoilers and reversers deploy, you can really feel it at the controls but from outside it looks very subtle, as in the videos below.

https://youtu.be/2ZPM6nTJkpg

at 00:56

https://youtu.be/6xwUPvjW5Qk

at 02:14 and 02:52

I've never had the yoke all the way back but certainly wouldn't push forward at all, if anything you're trying to let the nose down as gently as you can before you slow down too much. As Jon mentions above that could lead to the nose touching down quite hard. At most, you'd release back pressure but no pushing.

[Britjet]

No rules.
Once you've eased the nose down to contact, (which might mean a bit of back pressure) just let go.
Peter

[Hardy Heinlin]

Thank you for the comments, guys.

"Wheelie" -- I'm not sure what that means. Guess it's a random effect. But what axis? Yaw or pitch?

I remember, long time ago, in my first 744 sim sessions I once held the nose up for too long, and I had just enough elevator available to make a smooth nose gear touchdown in the last second, with the elevator at the max. And that was on a short runway with autobrakes 4. I know some guys at Northwest Airlines and El Al sometimes kept the nose up till the end (on long runways), and I always wondered if it isn't a bit risky :-)

By the way, my initial question re "nose down pressure" refers to the phase after nose gear touchdown.


|-|ardy

[Mariano]

Hardy,

😂 "Wheelie" is (an American?) term that describes when a motorcycle is made to stand on its rear wheel (front wheel completely off the surface).

Best regards,

Mariano

[Hardy Heinlin]

Aha!

[localiser]

Aha!

Hardy, I meant a momentary nose up pitch, you can probably make it out best in that BA video in the link above.

Once the nosewheel is down, the only control input would be into wind aileron

[Hardy Heinlin]

I immediately understood your words: "I find the 744 tends to pitch up when the spoilers and reversers deploy ..."
(And I'm aware of this effect.)


I just didn't get the meaning of Jon's "Wheelie" word :-)