Linked Questions

49 votes
3 answers
21k views

Why does supersonic flight detach airflow from a wing?

I've read in several answers to questions that when a wing passes the speed of sound the airflow will become detached from the craft towards the rear quarter of the wing (thus making things like ...
Jae Carr's user avatar
  • 24.2k
48 votes
3 answers
34k views

What is this flange on the engine?

Flying home from the Denver ComiCon, on a 737, I saw an angled flange on the engine. Could you describe its purpose? Photos by CGCampbell licensed CC0
CGCampbell's user avatar
  • 11.1k
31 votes
3 answers
10k views

What is the immediate cause of stall?

The direct cause of stall is unclear to me. I heard about exceeding maximum angle of attack (around 40°) ; I heard about reaching the stall speed in the current configuration (flaps, etc). I heard ...
Fox's user avatar
  • 1,811
24 votes
2 answers
4k views

Is a golf ball surface a good idea for wings or fuselage?

I searched for an infamous golf ball question on this site but did not find any, so I guess it's time for one. Would a dimpled surface like a golf ball somehow improve the aerodynamics of an airplane?...
DrZ214's user avatar
  • 17.8k
18 votes
2 answers
3k views

Why does this Strikemaster have a textured leading edge?

I was at Duxford recently, and spotted a Jet Provost Strikemaster that had a rough texture applied to a portion of the leading edge of the wing. Why was this applied?
Sam's user avatar
  • 425
10 votes
1 answer
2k views

What are these four little things between the horizontal and vertical stabilizer on the B737?

I was looking at some photos today and came across this one: Image source I noticed four little things in between the horizontal and vertical stabilizer. Could somebody explain me what those are?
Andrew's user avatar
  • 101
10 votes
2 answers
6k views

How does the position of vortex generators on engine cowlings affect flight?

I know what vortex generators (VGs) do. My question is: How come some aircraft have VGs on both sides of the engine, whereas other aircraft have them on the inside only? For example, in this picture ...
ROIMaison's user avatar
  • 7,427
18 votes
2 answers
3k views

What is the purpose of the fin at the Boeing 787 APU exhaust?

The fin is located under the Boeing 787 APU exhaust as shown in the picture below. Does anybody know the application of this thing or it is used for 'guiding' the APU exhaust? Thanks.
Chaintawit Singkaew's user avatar
2 votes
1 answer
1k views

What are these diagonal devices above the leading edge of the V-22 Osprey's wing?

The Osprey has some kind of aerodynamic devices sticking up along the top of the leading edge. This picture from the Wikipedia page of the wings rotated shows them against its silhouette:- Public ...
Dan Hulme's user avatar
  • 12.7k
8 votes
2 answers
572 views

Are there any aircraft with retractable vortex generators?

From this answer, “Of course, these also add drag, even when the wing is not stalling, so they are only added where needed”. Are there any aircraft that have vortex generators that are retractable so ...
dalearn's user avatar
  • 2,263
3 votes
1 answer
2k views

What is the "No Step" flap thingy used for on an A320 engine? [duplicate]

There is a small plate sticking out of an A320's engine narcelle with "No Step" written on it. I tried taking a picture of it, which in retrospect didn't turn out as good as I wanted it to be, but I ...
JustSid's user avatar
  • 1,616
0 votes
1 answer
460 views

Is a 20% forced transition in xfoil similar to adding a vg?

Is a 20% forced transition etc. in xfoil similar to adding a vg? I understand a 20% forced transition in xfoil, is tripping the boundary layer from laminar to turbulent. Isn't that what a VG does? ...
Fred's user avatar
  • 1,507
0 votes
1 answer
153 views

What provides a higher lift to drag ratio, a thick laminar wing or a thinner wing with a vortex generator

Recent readings have shown the benefits of "boundary layer tripping devices" or vortex generators for reducing drag and maintaining attached air flow at higher angles of attack. It seems these ...
Robert DiGiovanni's user avatar