Descent rate control (Electric)

[Cruiser]

Does anyone know what this is? I was looking at my equipment list and it is marked as installed when manufactured. There is nothing in the log books about removal. The reference drawing is #950271 and it weighs 12.8 pounds!

[BorealOne]

Those would be your speedbrakes - they are listed in the same way in the POH in my O.

[Cruiser]

Duh!.

[Marauder]

Duh!.

 

Don't you just hate it when they play verbal semantics like that?

[carusoam]

Is that marketing or legal semantics?

I was thinking the A/P can be set to descend/climb at rates in chunks of 100fpm...

And the system is electric.

Glad the answer was posted before I found this thread...

Best regards,

-a-

[Hank]

Semantics? Do speedbrakes actually reduce airspeed? I've only seen them increase descent rate.

[Houman]

Belive me it reduces the airspeed, you can feel it on the seatbelt when you put it on, it reduces about 20 kias in a mater of 3 seconds....

I use it on the rocket to slow down while keeping the engine MP higher so that I can keep with the recommanded reduction of 1 MP per minute..

[carusoam]

Physics conundrum....

They definitely convert energy.

The pic has the option to choose to convert, kinetic or potential energy (or a combination of both) to heat, using friction induced by the 'speed breaks'...

When too high... Deploy speed brakes...

When too fast... Deploy speed brakes...

When too high and too fast... Deploy speed brakes...

When negotiations with ATC fail (resulting in the slam-dunk)... Deploy speed brakes...

The operational word 'too' implies that an ordinary Mooney Pilot plans so well, he is not too high or too fast very often.

It does provide a nice way to slow down and go down while keeping CHTs warm...

Deployable up to 165, possibly Vne(?).

Best regards,

[Houman]

Carusoam, are you sure they are deployable up to Vne ??? I had understood that it can only be deployed when in the green arc or something to that effect... If I'm in the Yellow Arc ( which is often with the Rocket ), then I reduce the MP by 1 or 2 degrees to slow down to the Green Arc, then deploy the speed breaks...

 

I have to read my POH again, but I kind of have fuzzy memory reading about a deployment speed limit on the speed break when I first went trough the POH after getting the plane.

 

Thanks for the clarifications...

[Marauder]

Physics conundrum....

They definitely convert energy.

The pic has the option to choose to convert, kinetic or potential energy (or a combination of both) to heat, using friction induced by the 'speed breaks'...

When too high... Deploy speed brakes...

When too fast... Deploy speed brakes...

When too high and too fast... Deploy speed brakes...

When negotiations with ATC fail (resulting in the slam-dunk)... Deploy speed brakes...

The operational word 'too' implies that an ordinary Mooney Pilot plans so well, he is not too high or too fast very often.

It does provide a nice way to slow down and go down while keeping CHTs warm...

Deployable up to Vne.

Best regards,

-a-

You got them on your"O"? I wish I had them on my F. With a VFe of 109 KIAS and a VLo of 104 KIAS, it can be a real pain to descend while trying to slow down.

[carusoam]

O-MSE...

Everything available in '94 accept AC and FIKI...

Going to POH to verify operating speed...

--------------------

Update....

I don't have a copy of the speed brake supplement in my office....

From the POH that I have on my iPad.....

Emergency descent procedure indicates gear operating speed is 140kias

Once deployed max gear operating speed is 165kias

Deploy speed brakes if equipped....

Anyone have the operating speed limits for PreciseFlight electric speed breaks?

Best regards,

-a-

The forces get pretty dramatic at higher A/S compared to pattern speeds...

[Cruiser]

MOONEY

M20J, M20K, M20M, M20R, M20S, M20TN

AFM SUPPLEMENT

SPEEDBRAKE 2000

REVISION B 12--28--2006

SECTION II -- OPERATING LIMITATIONS

AIRSPEED LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Same as the basic airplane

ICING CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . The use of Speedbrakes are PROHIBITED

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . during flight into known or forecast icing conditions

[carusoam]

Thanks Tom!

Now, I need to get internet at 12k'...

I'd like to pole the MS community.....

[Houman]

Thanks Tom, but what does that mean same as the basic airplane :

Would it mean that if you are in the yellow arc because you can get there and air is smooth and no turbulence, then you can deploy the speedbrakes at that speed ?...

 

I have deployed them being at the very top of the green arc and it is a hell of a slow down, the faster you go, the more air the speedbrakes encounter and create more drag I guess...

[RobertoTohme]

Under normal operation conditions, your limitation is Vne (red line); however, in an upset that results in Vne exceedance I wouldn't hesitate to deploy them...  Better have the airbrake mounting base bent than risking structural failure because of the overspeed.