Electric Gear Modification or Speed Brakes?

[Marauder]

One of the biggest challenges I have flying an F model is the low flap (VFe = 109 K) and electric gear speeds (VLo/VLe = 104 K). This is especially true if I am IFR and get slam dunked. Years ago I looked into what it would take to convert my gear to allow for J like gear extension speeds. I can't remember if it was purely a cost or lack of availability thing. Has anyone done an upgrade on a pre-J electric gear plane to obtain the higher gear speed?

 

Years later speed brakes became available. For those of you who did either mod, can you tell me how that worked out for you?

[Bob_Belville]

I have the manual speed brakes on my '66E. Precise Flight Inc STC SA5708NM. Done by a previous owner in 1997. Trouble free, can be deployed at any speed and very effective at high speed with much less effect when slow. All good. And compared to other choices relatively inexpensive.

[carusoam]

I have the speed brakes on the O. They are the same effect as described by Bob.

The O has higher flap and gear speeds but the cruise speed and altitude can put them out of reach. The speed brakes close the gap.

Yes, they are a terrible waste of energy. They are also a good tool to have, for whatever reason you may want them.

Electric ones require some clutch work over time.

Manual ones would go great with manual flaps and manual gear.

Check to see if in the emergency procedures if you can use full flaps, gear and brakes while slipping. Expect descent vertical speed under control below Vne is pretty impressive.

The Ovation leaves out the slips portion of the equation.

Best regards,

-a-

[Marauder]

So, what are the specifics? Bob -- I'm guessing your E has similar speed restrictions as my F. Lets say you are doing a 130KIAS and are in level flight. If you don't touch the power and toss them out, do they do anything to reduce your speed or do they only work in a descent attitude? If you are in a descent, what kind of change do you see in your FPM with them engaged?

[Bob_Belville]

B26, my gear restriction is the same as yours, 120 mph, my flaps are even lower - 100 mph. 

 

The brakes could be used in level flight to reduce speed but that's not all that useful. Where they are useful is in higher speed descent. In my E I am routinely cruising in the yellow arc, In smooth air I can push over the nose and pull back the power to 15-18" and with speed near red line get 500(?) fpm. But if I'm getting near the airport or if the air is bumpy enough to make red line not an option I can deploy brakes and see 1500 fpm without shock cooling engine. When I get to pattern altitude and level out the brakes will help get the speed down to gear speed. At that point I will retract brakes - the gear is plenty of drag to slow to pattern and flap speed.

 

I probably use the brakes on 1 flight out of 10. I used them returning from Maine last month when I had been maneuvering build ups, still IFR, and wanted to drop below the broken clouds. I used them going into Sun n Fun in April is a similar situation to get 1500 fpm while still bumping through the scattered layer in order to get down to where I could cancel IFR and join the herd arrival. 

[Marauder]

Thanks Bob for the detailed report. Years ago I tried requesting ATC to allow me to slow a bit before descending, but it met with mixed results. By knocking 20 or 30 knots off before descending, I was screwing up their flow -- unless I was flying to an out of the way airport. Since then, I have learned to ask for lower early. The worst combination for me is being 1000' above the IAF altitude, 5 miles or less out and within 20K of cruise. If I can get it slowed down to VFe, I'm good. Otherwise, it is pulling back a lot on the power.

[Bob_Belville]

Yeah, my first Mooney (also a '66 M20E but w/o brakes) was a problem arriving at my home base IFR, particularly from the west. The airport is 1266 but terrain to the west is well over 6000 and I'd be within 15 miles of the airport needing to loose 4 or 5000 feet. Back then the only approach, an ADF to rwy 3, required another 1000 fpm dive, often with a tail wind. (Cross the NDB @ 4000, 6 miles from the runway.) Brakes would have been a great help. Of course if I slowed to gear speed and put the gear down early I was OK but I was also going to be busy when I had to go missed.

[DaV8or]

I am curious as to what it takes to get the gear speed increased and how much it costs, but I think I would lean towards the brakes option myself.

[Marauder]

I am curious as to what it takes to get the gear speed increased and how much it costs, but I think I would lean towards the brakes option myself.

I'm curious as well. Is it just the gear door design that allows that to be possible? Or are there other factors like a beefier gear motor and hardware?