Interesting speedbrake movie

[FlyDave]

I just came accross this YouTube movie illustrating the disturbed airflow when speedbrakes are deployed on a Mooney (or probably most other wings that have speedbrakes installed):

[HopePilot]

People have read about the problem I had with my new speed brakes (the motor of my left brake kept running after it was retracted and had to be replaced), but that said, they are magical and have given me near super powers.  On one recent flight a controller forgot to remove my altitude restriction until I was right next to the airport.  No problemo.  Then on the way back, Burbank asked me to fly at slowest practical airspace for a 737 (the J is fast enough to cause separation problems as the jets slow down on final if I'm hurling towards the runway).  I extended the speed brakes and slowed from 160 to 100 in seconds.  I actually feel that I am distorting controllers, many who are not pilots, understanding of what instructions planes are capable of following.  They have already kept me safe when I needed to remain high over an obstacle too close to final.  Also, they really do work for slowing down (I know people have said they aren't technically brakes, but they actually serve that function very well, if you hold your altitude) or to lose crazy amounts of altitude (great for ducking under inconveniently placed clouds).  I think they're one of the finest speed mods you can buy as they allow you to rocket towards the airport without worrying about overshooting it.

[Mcstealth]

Quote: HopePilot

People have read about the problem I had with my new speed brakes (the motor of my left brake kept running after it was retracted and had to be replaced), but that said, they are magical and have given me near super powers.  On one recent flight a controller forgot to remove my altitude restriction until I was right next to the airport.  No problemo.  Then on the way back, Burbank asked me to fly at slowest practical airspace for a 737 (the J is fast enough to cause separation problems as the jets slow down on final if I'm hurling towards the runway).  I extended the speed brakes and slowed from 160 to 100 in seconds.  I actually feel that I am distorting controllers, many who are not pilots, understanding of what instructions planes are capable of following.  They have already kept me safe when I needed to remain high over an obstacle too close to final.  Also, they really do work for slowing down (I know people have said they aren't technically brakes, but they actually serve that function very well, if you hold your altitude) or to lose crazy amounts of altitude (great for ducking under inconveniently placed clouds).  I think they're one of the finest speed mods you can buy as they allow you to rocket towards the airport without worrying about overshooting it.

[HopePilot]

I didn't feel so lucky when my plane was in the shop for nearly three weeks...   

[Jeff_S]

I can see the advantage to speed brakes if you wanted to quickly slow down without kicking off the autopilot. But otherwise, have you noticed any major difference between the effect of speed brakes vs. a good old-fashioned slip? I can bleed off airspeed (or altitude, if necessary) in a hurry with a good slip. I'm curious if anyone has compared the effects of the two techniques.

[carusoam]

"I'm curious if anyone has compared the effects of the two techniques." Jeff_S

[1] Nothing beats a slip for slowing down and losing altitude.

[2] Nothing beats speed brakes for slowing down while maintaining coordinated flight.

My comparison, now shared....

-a-

As for the video...Great demonstration of how such a small device has a pretty large impact on aerodynamics.  Real good heads up by the folks that captured the details. (flying at night, in the rain, with enough light on the wing to see the effects clearly and give narration at the same time)

[GeorgePerry]

FlyDave:  very cool video.  I would have never guessed the redirection of airflow would effect an area so large and so far forward of the speed brake. 

I've flown Mooney's with and without speedbrakes.  Yep, a slip is just as affective as speed brakes to quickly bleed off excess airspeed and/or altitude.  The only drawback I've noticed to a slip is that passenengers, esp those who aren't pilots, don't really like the feeling of sideforce (yaw) and deceleration simultaneously. 

With that said, even when I fly a speed brake equipped plane I make a point to try not to use them.  Anytime they are deployed I feel like I'm waisting fuel and should have "planned" ahead better.  Although in the real world, sometimes controllers take flight management decisions out of our hands...then speed brakes are nice to have.

 

 

[fantom]

I'm glad I have speedbrakes, and that the only service ever required has been a squirt of TriFlow once a year....

I rely on them about as often as I slip my Mooney to slow down.

 

[HopePilot]

Well, I've never tried to do a hard slip at 160 knots (to slow down for turbulence, etc.) so I'm not sure how it would compare.  Do people actually do that?  In terms of slow speed altitude reduction, I find the speed brakes give you a much more stable approach than a slip.  Also, if you slip the wrong direction with less than 6 gallons of fuel in a wing, your engine could quit.  Passengers dislike that even more than the feeling of uncoordinated flight.

[FlyDave]

Quote: GeorgePerry

With that said, even when I fly a speed brake equipped plane I make a point to trying not to use them.  Anytime they are deployed I feel like I'm waisting fuel and should have "planned" ahead better.  Although in the real world, sometimes controllers take flight management decisions out of our hands...then speed brakes are nice to have.

[jlunseth]

Its not different if you fly a turbo.  You just have to plan further ahead.  I typically start my descent between 50 and 75 miles from my destination airport, just tip the nose down.  No need for brakes most of the time.  When you do need to get down very fast though, they are indispensable. 

[Vref]

Quote: GeorgePerry

With that said, even when I fly a speed brake equipped plane I make a point to trying not to use them.  Anytime they are deployed I feel like I'm wasting fuel and should have "planned" ahead better.  Although in the real world, sometimes controllers take flight management decisions out of our hands...then speed brakes are nice to have.

[DaV8or]

Quote: fantom

I'm glad I have speedbrakes, and that the only service ever required has been a squirt of TriFlow once a year....

I rely on them about as often as I slip my Mooney to slow down.

 

[fantom]

Thanks, Jim. That was my subtle point.

Maybe too suble for some ;-)

[Bacachero]

Speedbrakes anyone?

http://cgi.ebay.com/ebaymotors/Precise-Flight-Speed-Brakes-Mooney-Aircraft-/250751502715?pt=Motors_Aviation_Parts_Gear&hash=item3a61f4497b

cheers!

[rbharvey]

One thing people forget with a Turbo, yes it is easy to plan a 500FPM descent way out and enjoy the ride, however flying IFR in the flight levels one will typically get 1200-1400FPM descents from controllers no matter how much pimping you give them to start down. Example over Orlando at 22k and need to get into Vero Beach, no amount of pleading will get you a descent until outbound towards Vero. Thats about 75 miles to loose 21000 feet at 220+ kts.....plus the GFC autopilot limits you at 180KIAS, this is where you need speedbrakes...still hurts to deploy em for all that fuel you are wasting.