Do Pilots Ever Crab Aircraft After Take-off?.... Options

[UALdave]

That certainly looks like what's happening in these two videos:

http://www.flightlevel350.com/Aircraft_Bee...Video-8215.html
http://www.flightlevel350.com/Aircraft_De_...Video-8214.html

The Beech 1900D looked like it was having trouble climbing after take-off ( ), and even the Dash 8 seems to "hang" in the air before climbing more and then making the turn.

[joecessna182]

In the flying that I do, it is very common to crab an airplane into the wind after take-off. Mainly this is done so that the airplane can remain over the runway rather than drifting in the direction that the wind is pushing the airplane. It is not very crucial when departing from an airport that has only one runway, but at the bigger airport where they may be running simultaneous departures off of parallel runways, remaining over the center line is key as to not impede on the other departing aircrafts flight path by drifting over the other runway. This can even be seen by pilots flying larger jets. Someone can correct me too if I am wrong, but airplanes generally have a tendency to "weather vane" right after liftoff if no rudder pressure is applied to keep the nose of the airplane parallel with the runway. I may be wrong, but that is how it has always felt when I am taking off with a crosswind.

[AirRabbit]

In the flying that I do, it is very common to crab an airplane into the wind after take-off. Mainly this is done so that the airplane can remain over the runway rather than drifting in the direction that the wind is pushing the airplane. It is not very crucial when departing from an airport that has only one runway, but at the bigger airport where they may be running simultaneous departures off of parallel runways, remaining over the center line is key as to not impede on the other departing aircrafts flight path by drifting over the other runway. This can even be seen by pilots flying larger jets. Someone can correct me too if I am wrong, but airplanes generally have a tendency to "weather vane" right after liftoff if no rudder pressure is applied to keep the nose of the airplane parallel with the runway. I may be wrong, but that is how it has always felt when I am taking off with a crosswind.

Joe - you are right. Almost all airplanes will "weather vane," at least some, when operating in a crosswind. But that weather vaning isn't enough to keep the airplane tracking the desired runway centerline extended - that takes a deliberate effort from the pilot. You are also correct about single and multiple runway operations. Most of the dual or tripple runway operations have departing airplanes fly a specific heading (as assigned) after takeoff. Most of the time the clearance is something like "after passing the departure end" or "at the inner marker," or some such specific point, and then a clearance is issued to fly diverging headings. This makes things less complicated for the pilots, and it insures a widening separation as aircraft depart the same airport. For example, departing an airport on runways 27L, 27C, and 27R, the clearance for the 27L departures might be assigned to fly a heading of 250 after departure; the 27C departures might be assigned to fly a heading of 270 after departure; and the 27R departures might be assigned to fly a heading of 290 after departure. This way all aircraft are flying diverging headings and, as the wind will be affecting each airplane similarly, the ground path will also be diverging - even though no one may be flying exactly the runway centerline extended.

[c150student]

A pilot will crab the aircraft after takeoff in the same way that he will crab it during final approach. It just means you can maintain the centreline.

I read somewhere though that if you are cleared takeoff and climb runway heading, that you do NOT correct for wind. Instead, you fly runway heading (i.e. not track), because then every aircraft will be affected by the same amount by the wind.

[sigitas]

A pilot will crab the aircraft after takeoff in the same way that he will crab it during final approach. It just means you can maintain the centreline.

I read somewhere though that if you are cleared takeoff and climb runway heading, that you do NOT correct for wind. Instead, you fly runway heading (i.e. not track), because then every aircraft will be affected by the same amount by the wind.

Interesting... in EYVI I sometimes get clearance as "climb on RW heading to 3000'..." and I always crab into the wind.
and the faster the aircraft, the smaller drift angle i.e. b735 would drift 0.5NM in 50NM distance, and c152 could drift 10NM in the same distance on constant heading.

[AirRabbit]

Interesting... in EYVI I sometimes get clearance as "climb on RW heading to 3000'..." and I always crab into the wind.
and the faster the aircraft, the smaller drift angle i.e. b735 would drift 0.5NM in 50NM distance, and c152 could drift 10NM in the same distance on constant heading.

My suggestion for the next time you get a clearance that says "climb on RW heading to 3000 feet" is that you climb on runway heading until you reach 3000 feet. I say that because that is what the clearance says to do - maintain runway heading means turn your airplane to a heading that is the same as the runway heading. If the controller wanted you maintain a specific ground track, that is likely the clearance you would be given. Don't make your job of flying the airplane any harder than it is.

[Ranger]

I agree with AirRabbit. A clearance is a clearance is a clearance. When cleared to do something the pilot/crew is expected to do exactly that. Years ago, when I was a young pup pilot, the standard procedure for takeoff from the airport that I flew from was to maintain the runway centerline, i.e., crab into the wind to compensate for any wind drift. It made the departures a bit more challenging but it kept departures from over-flying noise sensitive areas. About the only thing that a pilot of a small aircraft has to do when cleared to 'maintain runway heading" is to sync their d.g. to the compass and comply.

[UALdave]

Interesting. With regards to air traffic; Terrace has got to be a pretty small regional airport; or at least it looks that way from the videos.

[talldude]

Look at all those "pilot only responses" wheres our ATC guys when you need them, like magnum where is that guy?

[glnflwrs]

Magnum hasn't been on this site since Nov. 9, 2006. I wonder why...

Talldude, are you in Beaver City? Hendley? Wilsonville? Devizes? Sappa Creek? Am I close?

[bernoulli]

Look at all those "pilot only responses" wheres our ATC guys when you need them, like magnum where is that guy?

I won't ever claim to speak for Magnum (or any ATC pro for that matter), but I can venture a guess as to how he/they would address this.

During the course of a shift running tower and/or departure, ATC will become intimately aware of what effect the winds are having on departing traffic and will issue departure instructions accordingly. If a "Fly runway heading" instruction is issued, ATC will more or less know beforehand what drift (if any) can be anticipated based on current winds and aircraft type. If there are simultaneous departures taking place on parallel runways, then this will factor into those departure instructions based on ATC's observations and educated judgement.

One thing I can be absolutely sure of, is that ATC does NOT want the pilot to take it upon one's self to take matters into their own hands by "helping" ATC by fiddling around with different indicated headings to obtain a track angle down the runway centerline, or assigned heading.

Just keep it simple and fly the assigned INDICATED heading. ATC will work out the rest.

[rjb4000]

One thing I can be absolutely sure of, is that ATC does NOT want the pilot to take it upon one's self to take matters into their own hands by "helping" ATC by fiddling around with different indicated headings to obtain a track angle down the runway centerline, or assigned heading.

Just keep it simple and fly the assigned INDICATED heading. ATC will work out the rest.

Been away for a while, but I'll give this one a go..
Most of the time when you see an airport departing and arriving on parallel runways you're looking at a busy class b or c airport. Most b and c airports have radar towers which put basically means that they can give you headings and such. As a side note, the "non-radar" towers can still issue headings upon departure, but they have been worked out beforehand to provide adequate separation prior to the radar facility assuming control.
Now most class b airports departing multiple runways have standard instrument departures which dictate headings and altitudes to guarantee departure separation. The towers that do not though will certainly take wind into account (remember of course that the wind will be generally blowing "down the runway" so it's slightly easier). What I find interesting is that most modern jets take into effect the wind and will fly the "track" heading rather than the "magnetic" heading so that they are flying the assigned magnetic heading corrected for wind while most G/A airplanes fly straight magnetic headings and are blown around by the wind. Now if you and I know that, you bet the controllers do . In summary, fly the magnetic heading, and keep your eyes open.