Speed brakes

[Phuz]

As a matter of technique, some people establish themselves on final approach with the speedbrakes deployed to the max in-flight <250kias. This technique burns additional fuel in getting you to the runway, but it allows you to simply retard the throttle to idle upon landing. In some aircraft it can also assist in a go-around as the engines are generally spooled up at a higher level in order to maintain the approach speed with the brakes deployed.

 

By far the biggest factors in your landing distance are going to be the speed you touch down at, and the location you touch down at. The speed at which you touch down is going to be affected by your weight and configuration. The location by your skill :joystick:

Edited August 4, 2011 by Phuz

[CupOHemlock]

They sure have saved my bacon a few times when I unwisely came in a bit too hot :)

[EtherealN]

Here's the comparison flight, finally got it uploaded. Please excuse the crappy flying. :P

 

[Lane]

Actually, they do have a pretty big effect, but in that scenario you'll only see the effect if you do a direct comparison between two landings. I'll see if I can make a track set to show this.

 

 

Agree with that, i use them for landing, and it make a big difference on the lenght of complete arrest .... i can pretty much stop before half the runway. ( using wheel brake ofc ) .

 

I like land, in slide mode, specially with a cross wind.... and speed brake help a lot for stabilise the plane in this case ( slide all along controlled with rudder, nose at 45°C of the runway, then correct before wheel touch down )

Edited August 5, 2011 by Lane

[Phrenesis]

Here's the comparison flight, finally got it uploaded. Please excuse the crappy flying. :P

 

Thanks for taking the time to make this vid. I didnt know they had this much effect on the ground. I never put them wide open after touch down, but will do from now on.

[Laud]

One advantage of overhead landing patterns is that you have enough time to take care for your speeds, altitudes and configurations at the different stages, so you'll mostly won't roll into final too high or too fast.

 

Overhead: 250KIAS/1500ft AGL -> 180° turn into downwind: bleed speed to about 200KIAS, remain 1500ft AGL -> When RWY-treshold is at your 3/9 o'clock (depending on whether you're performing a right or left hand patern): extend gear, flaps, and set airbrakes to 30-40%, add some throttle so you don't get below 180KIAS -> When RWY-treshold is at your 5/7 o'clock: roll in to final, let the nose drop below the horizon (about 5-7° pitch down) and reduce throttle so that you slowly reach approach speed (according to your aircrafts weight) -> on final set your TVV on the RWY treshold, watch speed go slowly towards your desired touchdown speed (depending on your aircrafts weight), recheck your gear is down and locked, flaps and brakes are set as desired -> short final: monitor speed (correct throttle as neccessary) and begin to flare (ideally pull the TVV to the desired touchdown area) -> touchdown: reverse throttle to idle, fully extend the airbrake and keep some pull on the stick to avoid the nosewheel slamming into the ground -> let the aircraft slow down to 100-80KIAS before starting to gently apply wheelbrakes -> once below 50 KIAS: retract flaps and brakes, apply NWS and vacate the RWY.

 

That's our squadrons (and partially RL) landing procedure. I always see my aircraft slow down well by extending the airbrakes to 100% after touchdown and not using the wheelbrakes before getting below 100 KIAS.