Static vs Rolling Takeoffs

[Bjammin]

Alot of fighter type airplanes will slide forward on locked brakes at max power. Kinda tough to do a max power check and wipe out before T/O. I don't think any US fighter can still put in afterburner. Wet runway? forgeta'boutit.

 

[Wiggums]

Early Lears, when light, will also slide when trying to do a static takeoff.

 

[Snakum]

Heres a question, is it easier to set power when you're static? Single pilot in a King Air I would think it would be somewhat difficult from a rolling start to stay centerlined, move the throttle levers forward and be watching the engine instruments at the same time.

It did take a bit of getting used to, especially considering that the power levers on the B200 I fly are not rigged symetrically (left must be 1/2 - 3/4 farther forward for symetrical power). But I am very, very low time and I got used to it, so for most full-time pros it wouldn't be an issue at all, I'd think. The Captains I tag along with all do it quite smoothly, with no thought whatsoever.

 

[coloneldan]

When I was going through recurrent on LR-35's, FlightSafety said you had to have at least 10% more than minimum required to do a rolling takeoff. I think they used the same figure for the 20's also. However, I never saw that in writing anywhere.

I my opinion, if you have enough time in the airplane that you're comfortable, and enough runway for the conditions that you feel safe, there's no reason not to use a rolling takeoff along with a reduced power setting. But, if anything happens, you better be able to stop or clear the obsticle. If not and you survive, there are going to be questions to answer. So, CYA.

 

[MauleSkinner]

In Falcon 50 school they told us that unless you hold the brakes and set the power, that the DEECs won't let the engine provide advertised takeoff thrust for something like 3 minutes after you push up the thrust levers. Thus the reason to get on the runway and hold the brakes. Actually I'm confused. How does anybody actually do a "static" takeoff? Do you sit in the cockpit and make airplane noises or something? Just kidding...

EB

My understanding is that the 3 minutes is simply the number that the FAA chose to allow for certification...you can sit on the runway with the thrust levers full for 3 minutes before doing your certification takeoffs.

According to my SimCom Hawker book, "When using a rolling takeoff, reduce the available field length by 100 feet." IOW, plan on an extra 100 feet of ground roll. Not that big a deal on most runways.

I'm nowhere near the airplane now, so I can't actually verify that with AFM data, but I'm guessing it's a reasonable facsimile of something in the AFM performance section.

Fly safe!

David

 

[time builder]

Heres a question, is it easier to set power when you're static? Single pilot in a King Air I would think it would be somewhat difficult from a rolling start to stay centerlined, move the throttle levers forward and be watching the engine instruments at the same time.

I was thinking along the same lines, the BE99 I flew required us to parallel the torques at 400 ft/lbs a side before advancing to takeoff power. If you don't, you're more likely to have one side spool up faster and jerk you off the centerline.
You can do it on the roll, its not that hard if you're familiar with the plane, but I'd imagine you'd use more runway from the time spent rolling at low torque.

 

[Mason]

If this has any bearing on anything I believe that all AFM T/O numbers are based on the power being set by 80kts.

 

[MauleSkinner]

If this has any bearing on anything I believe that all AFM T/O numbers are based on the power being set by 80kts.

I think that may be an erroneous assumption...everything I've seen indicates power takeoff power set prior to brake release to make chart data.

From my SimCom Hawker book:

Associated conditions...

...Both engines are run up to initial maimum take-off power and then brakes are released....

Obviously, this isn't from the actual AFM, but I'm betting again that a reasonable facsimile exists in the AFM.

As far as the power being set by 80 knots, this is probably listed as a rolling start technique, but that's a technique that takes you away from performance chart data.

Fly safe!

David

 

[Mason]

I think that may be an erroneous assumption...everything I've seen indicates power takeoff power set prior to brake release to make chart data.

From my SimCom Hawker book:

Obviously, this isn't from the actual AFM, but I'm betting again that a reasonable facsimile exists in the AFM.

As far as the power being set by 80 knots, this is probably listed as a rolling start technique, but that's a technique that takes you away from performance chart data.

Fly safe!

David

Ok, maybe my info just applies to a certain type.

 

[cvsfly]

It did take a bit of getting used to, especially considering that the power levers on the B200 I fly are not rigged symetrically (left must be 1/2 - 3/4 farther forward for symetrical power). But I am very, very low time and I got used to it, so for most full-time pros it wouldn't be an issue at all, I'd think. The Captains I tag along with all do it quite smoothly, with no thought whatsoever.

Same with our B200. Not rigged symetrically. Sqwauked several times in the past years and never corrected perfectly. We now live with it. With experience and proficiency it is not a problem. Typically King Air pilots bring power up on the brakes until the props are on the govenors (2000 rpm) and then release and then push up power due to varying spool up times of the props/engines. If you are smooth there is no reason to have any variation and stay on centerline. If you jam them forward you will get unsymetrical power (and the amount of variation may change due to density altitude). This happened the other day to us with our other pilot flying and he aborted the take-off (rightfully so, but takes some explaining to the pax). He is thinking it was something wrong with the engines, but it was technique.

 

[Gorilla]

Our manual states that a rolling T/O has a negligible performance difference vs. a standard T/O.

In the 737, especially the NG aircraft, the intake lips are so low to the ground, I'm surprised they don't FOD more. We never jack the power up all the way unless we have some velocity, and especially on landing roll, you get out of reversers by 60 knots to avoid FOD unless stopping distance is critical.

As the other guys have said, it is AC specific, but I think the general gist is if the AC can handle it mechanically, a properly executed rolling TO doesn't hurt and I think is more comfortable for pax and easier on the jet.

 

[MauleSkinner]

Ok, maybe my info just applies to a certain type.

Which type, if I might ask?

David