Low Speed Buffet

[BeechDawg]

Does anybody have any idea what low speed buffet is? Is it the same as stall buffet? What do you all think?

 

[Turtlesfly]

the buffet before the stall - worded that way because it's assumed you're never going to get to the stall . . . it's a certification issue with Part 25, which is also why you practice "approaches to stalls" to the buffet, as opposed to full stalls like in your 172.

Cheers

 

[JustaNumber]

Does anybody have any idea what low speed buffet is? Is it the same as stall buffet? What do you all think?

Reason: What he said...

 

[RJP]

Buffet or Boofay?

We have some of those out here. Especially when a bunch of overweight folks get in line for seconds.

 

[Doc Holiday]

If I remember correctly, a low speed buffet happens high at altitude when the airflow over the wing is near the sonic range. As the aircraft slows and the angle of attack increases, the air moving over the top of the wing speeds up until shock waves form. These shock waves are like the ones that occur when a wing moves too fast through the air, or mach buffet.

 

[Turtlesfly]

Uhhh. No. I don't know, maybe you were joking.

From the 737 Performance manual: "High speed buffet is caused by supersonic airflow over parts of the wing. Low speed buffet results from an increase in angle of attack to the point where the airflow separates from the wing."

Sorry, this is just an ordinary stall - no shock wave, just separation.

However, the reason you have to look it up if you're high and heavy is because you wouldn't ever know off the top of your head the bank-angle-buffer that has to be built in to the minimum cruise speeds - especailly as expressed in Mach.