Simviation Forums

by **Rich H** » Sat Jul 04, 2009 10:38 am

What does it mean when people talk about a plane's Alpha, and usually fighter plane's one?

by **Dr.bob7** » Sat Jul 04, 2009 10:46 am

In real life Im not sure and ive never heard of it before, on the Flight sim forums the planes alpha is a channel in the textures that makes the plane reflective and the windows transparent

by **Isak922** » Sat Jul 04, 2009 11:30 am

In reference to real flight; It could be referring to high "Angle of Attack" maneuvers. In planes that have a gauge to show your current AoA, it's usually marked by the "Alpha" symbol (It's a weird looking "a")

The Angle of Attack of an Aircraft, is when put simple, the difference between the direction the plane is flying in (Straight and level, for example), and the current pitch of the plane (Say... 45 degrees).

In that example, the plane is flying straight and level, with little change in altitude, but the plane itself is positioned in such a way where that it's pitched up quite a fair amount. The simple way to put it, is a 45 degree Angle of Attack.

Some of the newer planes (Su-37, Su-35, MiG-35, F-22A) can fly straight and level, with even higher AoA's, sometimes even vertical (For a short period of time).

If you've ever heard of and seen the Pugachev Cobra in action (Youtube it), a maneuver very commonly done by Russian fighter aircraft; You'll already have a perfect idea of what it looks like as far as visuals go.

by **expat** » Sat Jul 04, 2009 1:50 pm

Alpha is the angle between the cord line of the wing and the airflow hitting the leading edge. The cord line is an imaginary line the cuts through the profile of the wing from the leading edge to the trailing edge. There are also a whole bunch of others, but that would cloud the issue here.
This is one of those times when Wiki can do a better job than most of us.
Picture top right, cord and hitting airflow

Matt

by **beaky** » Sat Jul 04, 2009 2:07 pm

Alpha is the angel between the cord line of the wing and the airflow hitting the leading edge.

Also known as the angle of attack. ;D

by **expat** » Sun Jul 05, 2009 1:33 am