videns
Posts: 132
Joined: Thu Mar 18, 2004 3:28 pm

More Wake Vortex Questions...

Fri Sep 10, 2004 3:38 pm

What would be the effect of flying thru a wake vortex from the side, instead of from behind the aircraft that created it? I know it depends on the angle, but I'm assuming the flight path being at 90 degrees with respect to the aircraft creating the wake vortex...
Also, for the vortex to be strong, it would have to have been created little before another aircraft crosses it, so is it feasible for an aircraft to actually cross such a vortex?
And yet more... I've seen airplanes flying very close to the plane I was on, in the opposite direction during cruise (probable 1000 Ft separation). I understand that wake vortex generation is higher at higher angles of attack and slower speeds, but during cruise, is it a cause of concern?

I'll appreciate any answers, and please correct me if I'm wrong in any of the above statements...

v
Travel? Why would i travel if I can watch it on TV?
 
FredT
Posts: 2166
Joined: Thu Feb 07, 2002 9:51 pm

RE: More Wake Vortex Questions...

Fri Sep 10, 2004 4:47 pm

It’s not really a problem in cruise. As you stated, the vortices are weaker and the speeds of the aircraft are also higher, meaning any vortice encountered will have less impact (less time to act and more kinetic energy in the affected aircraft).

The same goes for the crossing of a vortex at a right angle. You’ll be in the vortex for such an immensely short time that it won’t really have time to do you much harm at all... unless you are in a really slow, small and light aircraft in which case you’d get a pitch disturbance.

The vortices linger longer than you’d think so the distances don’t have to be all that small.

Regards,
Fred
I thought I was doing good trying to avoid those airport hotels... and look at me now.
 
Logan22L
Posts: 4464
Joined: Fri Jul 16, 2004 5:59 am

RE: More Wake Vortex Questions...

Sat Sep 11, 2004 12:22 am


Let's assume a take-off speed for a heavy of 150-160 knots, and a typical 2 minute separation used for take-off behind a heavy. Let's say the average speed of the heavy over these two minutes after take-off is about 250 knots. This means it is travelling approximately 4 miles/minute. Thus, it seems reasonable that typical in-flight separation could result in a plane passing through a wake perpendicularly, or at some angle. That said, FredT's reply seems right on the money, probably not a problem.

Logan
"The deeper you go, the higher you fly. The higher you fly, the deeper you go."

Who is online

Users browsing this forum: BHM, nwcoflyer and 15 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos