Telling tower about a very long takeoff roll?

[Ignition Override]

This might seem a silly idea, but certain control towers in the uS are under strong pressure to mix so much arrival/departure traffic, that it would help them to realize that a DC-9 40 or 50 series using a 5 degree flap setting can result in using most of the runway. The problem with trying to advise them is that first of all, I can't remember other pilots mentioning this on tower freq and trying to advise tower can result in a blocked transmission.

Do any Tower Controllers see this info as a benefit with heavy arrival traffic to both runways (i.e. MSP ), or is not worth the risk of a blocked transmission?

[Scott Voigt]

I haven't worked tower in a while, but I would rather know if you weren't going to roll vrs. the longer takeoff roll. It may add a couple of seconds before we can clear the next one for takeoff ( got to wait for that nose wheel to come up <G> ) but in these days of heavy radio traffic, the controller will probably be happy with just seeing you roll down the runway... We already know that with some of the older jets we are going to see some longer rolls...

regards

[FWA NATCA]

Ignition,

Use 1/4, 1/2, or the entire 12,000 feet of the runway, I don't really care as long as you get that thing up in the air. Seriously, the only thing that using the entire length of the runway causes is a slight delay for me to clear the next guy for takeoff, or in a rare occasion someone on short final may get a go around because you are not airborne yet.

I'm use to freighters taking the majority of the runway for their take off rolls so a long take off roll doesn't bother me.


Mike
FWA

[pom]

Most of us use reduced thrust for takeff these days to extend engine life. This means we always use most of the runway, unless it's reeeeeally long ................

[Dan Dare]

If I expect a certain performance, but you are planning on using twice as much runway, it would be useful to be pre-briefed. That information could be used to put you further back in the queue though.

Scenario 1: Aircraft at 3 nm final when you are issued with take-off clearance from the hold. This should work under most circumstances so that the inbound gets landing clearance inside 1 nm. If you take and extra 30 seconds to lift the wheels, then the inbound may not get a clearance this time round.

Scenario 2: You lined up to depart with just enough space to get another one off behind you before the next inbound. Under favourable circumstances Number 2 goes as soon as there is daylight beneath your wheels. If you take significantly longer tahn expected then see scenario 1...

I agree that too much chat on TWR is a bad, but there is no reason not to notify the ground controller instead.

[mutt]

Dan Dare,

Can I ask what you are basing your certain level of performance on?

We are striving to get crews to use the least amount of thrust and the greatest amount of runway possible.

Are we on different wavelengths?


Mutt.

[Dan Dare]

Q. Can I ask what you are basing your certain level of performance on?

A. I should be able to make a judgement based on the aircraft type, operator, destination, conditions etc whether you can be squeezed off in the miniscule gap available between arrivals. This is sometimes very tight and can be down to (almost) split second timing. Poor judgement can lead to go-arrounds or worse. If the best of my information shows that I should be able to get you airborne in the space available, but you haven't told me that you are performing worse than normal, then I'll be a little upset (but not as upset as the guy on minimum fuel having to go arround on vapour).

We are well aware that you use assumed temperatures and de-rate power etc, but I don't believe the question was about that. I also don't think that there can be many places in the "civilised" world that don't have noise regulations for clinb angles to get you away from the NIMBYs ASAP. As for using the greatest amount of runway possible, I have never seen evidence of any pilot doing that (Perf A would also suggest otherwise).

What then is the answer?
Always use bigger gaps? That reduces the number of available movements (therefore unlikely), but is used for individual aircraft requiring it.
Tell the controller that you may need more runway? BINGO - takes 5 seconds of RTF time and allows the controller to set up a bigger space for you!

[Ramble off]

[FWA NATCA]

Mutt,

Basically a certain level of performance to me means that a Cessna or Piper will be airborne within 2500 feet, a King Air within 3000 feet, a Lear or Citation within 4000, DC-9 or B727 normally within 6000, a heavy within 6000.

As for Cargo aircraft (B727's, A300's, B747's etc) all bets are off, because I've seen some become airborne within 5000 feet or less, and others I wondered if our 12,000 foot runway was going to be long enough.

Mike