Boeing 757 turn rate?

On Mon, 14 Jun 2004 08:08:01 +0200, Bas Jansen
wrote:

Arbr64 wrote:

The Standard Rate Turn is a concept created a long time ago to standardize
turns so that they are predictable for both piltos and controllers.
They allow a pilot to perform any course change or turn while flying in
clouds without a compass or a heading indicator.
For instance, to change heading by 30 degrees, the pilot executes a
10-second Standard-Rate-turn if it's a small airplane, or a 20-second turn
in a jet.
The Standard Rate Turn is the rate-of-turn used by the autopilots when it
executes turns.

The standard rate turn is just that... a _standard_. No use for a
'standard' if it differs from airplane type, right? A standard rate is
the same across the board. Whether it be an airliner or a small single
engine prop...

This is the reason the Standard Rate turn in a jet is 1.5 degrees per second
or 4 minutes for 360 degrees turns.
Just a quick note : Airliners execute turns of AT LEAST 30 degrees bank
every time, except when performing small course corrections while in cruise.

I'm sorry but you're wrong here. The autopilot logic regarding
bank_angle is more or less the same for every passenger plane. I fly the
Boeing 737 5 days a week and it never exceeds 30 degrees of bank except
when it intercepts a localizer or VOR radial at a high angle... When
it does it certainly won't exceed 35 because warning bells would go off
(voice warning "bank angle!").

In order to maintain a standard rate turn the required bankangle will
increase as speed increases. I don't have the formula here but I can
tell you that if your doing i.e. 300kts you need more than 25 degrees to
maintain a standard rate turn. Airlines try to keep a standard rate turn
except when it requires a bankangle steeper than 25. The reason is,
primarily, passenger comfort.

In cruise the bankangle depends on the autopilot mode. Usually its in
LNAV (lateral nav. mode) whereby the autoflight system is coupled to the
FMS or RNav system. In that case the bankangle limit is set at 15
degrees (or some low value depending on aircraft type). If the
autoflight system is in HDG (heading mode) it limits bankangle to
whatever is selected on the flight director panel. Usually 25 degrees
with a maximum of 30 degrees and a minimum of 10.


Where did you get this from ? There is no such thing. Airliners execute 45
degree banks on every flight.

No they never do, see explanation above.

25 degrees of bank doesn't produce much of a heading change in a jet, test
it yourself in FS.

Mickey$oft FS is crap. Are you trying to prove your point by referring
to a game?

I turn with 25 degrees or LESS almost every day and I have no problems.
I have yet to have a controller yell at me for turning too slow. As a
matter of fact, if I were to turn with 45 degrees of bank I'd be in the
chief-pilots office the very same day... and it won't be a social call!

Zatatime, don't listen to what Arbr64 says. I don't know where he gets
his information from but he either misunderstood or has no clue whatsoever.

Regards.


Thanks.. I had already lauged off his reply. I know someone who flew
the 57 and 67 for American for many years. He idn't go into as much
detail as you, but summarized the same facts. Usenet has to be taken
with a grain of salt many times. I appreciate your input.

z