Aerodynamic braking

[B-ONE27]

Ok, been pondering this one for a while now, so my experts please humor me as to why certain aircraft use aerodynamic braking(cool as h.e. double hockey sticks I might add) when landing, and others simply bounce down on the runway without holding the nose high 3/4 of the way down the runway. Over the years I've noticed the occasional eagle or viper land, and there is the holding of the nose as the aircraft slows down upon landing...whereas I've also noticed a hornet or cat(gone but never forgotten) or prowler, even a hog land and place the main feet, followed by the nose gear feet almost immediately after touching down. Does this have anything to do with higher thrust aicraft...and finally how is this holding of the nose achieved by the pilot-can't imagine any jockeying of the throttles...but it must make for a cool arse ride

[Spongebob]

Well, first, aero-braking is hard to do if you're doing a carrier landing, or doing a carrier approach/landing to the field. It's not hard to do, you just hold the nose off the ground with the stick.

One thing you will generally see though, is multi-engine, non-centerline thrust aircraft have a minimum aerodynamic control speed for the ground (Vmcg), below which you need nosewheel steering to keep the puppy on the runway if an engine should fail. Additionally, bigger winged aircraft are more prone to lift a wing in a crosswind, and once again, having the extra control is nice.

Also, with thrust reverse/beta, it's rare to get all the engines trimmed well enough to give the same amount of thrust, and nosewheel steering is your friend then.

HTH

Spongebob

[tomthegrom]

I have seen footage of a-6s and tomcats aero braking. It always looks cool.

[SimFixer]

Can't speak to all the techie stuff that Spongebob listed but for the Eagle and Viper anyways, aerobraking is SOP except in certain emergency scenarios. It maximizes wheel and brake life just by its very nature.

[jmel]

A lot of it is also pilot technique/preference. I'll almost always do it as long as I can, simply because it decreases wear and tear on the jet's brakes. However, if the runway is a bit shorter than usual, I'll lower the nose and honk on the brakes.

Jake

[Karl Sander]

It CAN be done in the Prowler, just not all that common. Generally pilot preference/technique.

[David Walker]

Me and my buddy used to open the doors on his 1970 Capri to slow down....does that count?

The question would be how'd you ever get it to speed up in the first place? A friend of mine in high school had one and I'd only catch a ride with him if I didn't have to be anywhere in a hurry.

[Karl Sander]

The question would be how'd you ever get it to speed up in the first place? A friend of mine in high school had one and I'd only catch a ride with him if I didn't have to be anywhere in a hurry.

Steep hill and neutral???

[GreyGhost]

Me and my buddy used to open the doors on his 1970 Capri to slow down....does that count?

Ha, a buddy and I use to do that in his mom's 85 Isuzu Impulse GT too ... Fun times ...

Gregg

[Chris Kethan]

The question would be how'd you ever get it to speed up in the first place? A friend of mine in high school had one and I'd only catch a ride with him if I didn't have to be anywhere in a hurry.

Always remember David, "better a poor ride than a proud walk".

Chris

[Ben Brown]

Me and my buddy used to open the doors on his 1970 Capri to slow down....does that count?

We tried that in a Cessna once.

Spongebob's comment about the engines not coming up to full thrust at the same time was spot on. The CRJ's engines were especially bad about that. I had gotten used to the Beechjet's engines coming up at the same rate, so you could hold the nose off and wind the engines on up in reverse thrust. The first time I tried it in a CRJ, I scared the heck out of both myself and the captain. After that, the engines stayed in idle until the nose wheels were firmly on the ground!

I'd be afraid to try it in anything that didn't have centerline thrust, but I don't recall there being anything in the 737's limitations about using reverse thrust with the nose wheels off the ground.

Ben

[Flankerman]

About a million years ago - when the International Air Tattoo was hels at RAF Greenham Common - back in the 70's.......

One year's display had an F-14 from a Med-based carrier - and an F-15 (presumably from Lakenheath?

Anyway, they both put on superb flying displays - each one trying to 'outdo' the other - Navy vs Air Force.

I remember the hooha created when the F-15 'bent' his turkey feathers doing a long nose-high run using aerodynamic braking - lots of sparks from the tail area.

(or was it the Tomcat?? - memory fades when you get old..... )

There must be a photo somewhere......????

As an aside - the Russians seem to use braking parachutes a lot more than western forces.

It must also reduce brake wear - and seems to be a cheap, easy way to reduce the landing roll.

Some European jets (Tornado, Viggen spring to mind) use thrust reversal to reduce the landing roll.

just my two penn'orth.

Ken

[Impatient Pete]

Me and my buddy used to open the doors on his 1970 Capri to slow down....does that count?

Ha HA! My brother and I did that once with two friends in a four door Honda Civic wagon. Each guy had a door. Well, we didn't see the cop right behind us! His first words were "You boys been drinking?". He asked us if we wanted hin to follow us home and talk to our parents.

Pete