Bank Angle Limits for 121
01-31-2013, 04:16 PM
#11
Moderator
Joined APC: May 2006
Position: ATP, CFI etc.
Posts: 6,056
The formula for load factor in turns in any aircraft is n= 1/cos(bank angle), a formula you may already be familiar with. Solving for bank angle you get arc-cos(bank angle)= 1/n.
Plugging in a few numbers using typical + load limits for transports,
arc- cos (1/2.0) = 60*
arc -cos (1/2.5) = 66.4*
But as mentioned above, there are other things to consider. If for example the airplane loses nav reception at high angles, or it is shown that the aircraft has poor flight characteristics, or if the gust envelope doesn't work out too well, lesser limits may be applied.
Plugging in a few numbers using typical + load limits for transports,
arc- cos (1/2.0) = 60*
arc -cos (1/2.5) = 66.4*
But as mentioned above, there are other things to consider. If for example the airplane loses nav reception at high angles, or it is shown that the aircraft has poor flight characteristics, or if the gust envelope doesn't work out too well, lesser limits may be applied.
01-31-2013, 04:18 PM
#12
Gets Weekends Off
Thread Starter
Joined APC: Aug 2011
Posts: 484
Originally Posted by Cubdriver
The formula for load factor in turns is n= 1/cos(bank angle), so solving for bank angle you get arc-cos(bank angle)= 1/n.
Plugging in a few numbers using typical + limits for transports,
arc- cos (1/2.0) = 60*
arc -cos (1/2.5) = 66.4*
But as mentioned above, there are other things to consider.
Plugging in a few numbers using typical + limits for transports,
arc- cos (1/2.0) = 60*
arc -cos (1/2.5) = 66.4*
But as mentioned above, there are other things to consider.
02-01-2013, 04:46 AM
#13
Gets Weekends Off
Joined APC: Jul 2012
Posts: 737
Manufacturers build in squawkers/yoke force devices to limit bank angle. In a 737, the ADI (IIRC) goes amber in parts, and a stupid male voice starts to squawk "bank angle, bank angle". In the 777, you must apply extra yoke force to get more than 30 degrees.
I know this doesn't answer the FAR question, but Boeing and Airbus mechanics and software tend to keep things less than 31 degrees. I also agree that much more than 30 makes people scream in back. They are very sensitive to load, and when things aren't very close to 1.0 g, they get pretty upset.
I know this doesn't answer the FAR question, but Boeing and Airbus mechanics and software tend to keep things less than 31 degrees. I also agree that much more than 30 makes people scream in back. They are very sensitive to load, and when things aren't very close to 1.0 g, they get pretty upset.
02-01-2013, 06:30 AM
#14
Gets Weekends Off
Thread Starter
Joined APC: Aug 2011
Posts: 484
Originally Posted by ForeverFO
Manufacturers build in squawkers/yoke force devices to limit bank angle. In a 737, the ADI (IIRC) goes amber in parts, and a stupid male voice starts to squawk "bank angle, bank angle". In the 777, you must apply extra yoke force to get more than 30 degrees.
I know this doesn't answer the FAR question, but Boeing and Airbus mechanics and software tend to keep things less than 31 degrees. I also agree that much more than 30 makes people scream in back. They are very sensitive to load, and when things aren't very close to 1.0 g, they get pretty upset.
I know this doesn't answer the FAR question, but Boeing and Airbus mechanics and software tend to keep things less than 31 degrees. I also agree that much more than 30 makes people scream in back. They are very sensitive to load, and when things aren't very close to 1.0 g, they get pretty upset.
Now, to convince the ACP...actually, he's very open minded about stuff.
Thread
Thread Starter
Forum
Replies
Last Post
