Beta in a piston?

Yep. Very few people are certifying it these days, but it's completely doable. Seaplanes are the biggest market.

I always wanted it for the 310. Looking forward to it on the MU-2.
 
Don’t think it would do me any good on the Liberty.
 
There's a nice Husky on floats with that. Close the windows/vents before using or you get wet...


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Some seaplanes have reverse on the props, not for use in flight, but to make water handling a bit easier. Seen it on Seabees.
 
I've heard some of the Porter drivers use it to beat their jumpers back to the ground.

(When someone else is paying the maintenance bills)

3wayandplane.jpg
 
ElPaso Pilot said:
I've heard some of the Porter drivers use it to beat their jumpers back to the ground.

(When someone else is paying the maintenance bills)

3wayandplane.jpg
Click to expand...
I'm confused. How would reverse help you beat the jumpers to the ground. You'd want to go fast, not slow down.
 
ElPaso Pilot said:
I've heard some of the Porter drivers use it to beat their jumpers back to the ground.
Click to expand...
I heard the C17 tactical descent also allows for use of reverse thrust in flight
 
jkaduk said:
I'm confused. How would reverse help you beat the jumpers to the ground. You'd want to go fast, not slow down.
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bob's got it. Cross posting an example below. There are more stories out there if you look. Fact or fiction, who knows?


https://forums.flyer.co.uk/viewtopic.php?t=57939

Re: Pilatus PC-6 "Porter"#783272
By Chilli Monster - Mon Sep 07, 2009 3:00 pm
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There is a story of a Porter being used for paradropping which was going through engines every 400 hours. On investigation it was discovered that the pilot was putting it into reverse to get on the ground quickly - cooking the engine in the process. (PT-6's have a TBO of 3000 hours and are virtually bullet proof when operated normally!)

Having said that - put it into idle, stand it on its nose and pop out the brakes, RoD is pretty impressive with no damage to the aircraft. No need to do anything silly​
 
Swell.
Now I can run people down while reversing out of the dock.
Where do they put the mirrors, so you can see where you are going, or do they have a back up camera?

Honestly, I wish I had it 50+ years ago.
 
ElPaso Pilot said:
I've heard some of the Porter drivers use it to beat their jumpers back to the ground.

(When someone else is paying the maintenance bills)

3wayandplane.jpg
Click to expand...

And a few of those have come apart from people doing stupid pilot tricks.
 
Are you guys talking about beta or reverse? They are not the same. Beta is the prop in minimum thrust. Reverse is, well, reverse.
Edit, Sorry, should be min torque.
 
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Tantalum said:
I heard the C17 tactical descent also allows for use of reverse thrust in flight
Click to expand...
Min-reverse, so the engines stay at idle with the reversers deployed.
 
Ted DuPuis said:
Yep. Very few people are certifying it these days, but it's completely doable. Seaplanes are the biggest market.

I always wanted it for the 310. Looking forward to it on the MU-2.
Click to expand...

In the early 80s I worked about a hundred yards from Mitsubishi's HOU hanger, which I believe was their national sales base. There were always six or eight aircraft with MA registration on hand.

Anyway, I loved it when the MU-2s would taxi past with the pilots moving beta to control speed. The huge amount of noise the TPE-331s and props made had me grinning almost every time.
 
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Reactions: Ted
ronnieh said:
Are you guys talking about beta or reverse? They are not the same. Beta is the prop in minimum thrust. Reverse is, well, reverse.
Click to expand...
Technically beta in a PT-6 is when the prop angle is controlled directly by the power lever rather than by the governor, so reverse is a part of beta.
 
Nope, beta range by definition is prop angle producing minimum torque. Technically you can be in beta while in the air but in practice it is meant to be the blade angle on the ground that produces minimum torque. The range is useful to keep taxi speed down without punishing the brakes. I know many do use the term to describe all of the range behind the stops. I believe I have seen throttle quadrants on the Garretts with the beta range marked from stops to some distance rearward. But, beta is a specific blade angle and can change slightly with ground speed.
In my op I said thrust, should be torque, sorry.
 
ronnieh said:
Nope, beta range by definition is prop angle producing minimum torque. Technically you can be in beta while in the air but in practice it is meant to be the blade angle on the ground that produces minimum torque. The range is useful to keep taxi speed down without punishing the brakes. I know many do use the term to describe all of the range behind the stops. I believe I have seen throttle quadrants on the Garretts with the beta range marked from stops to some distance rearward. But, beta is a specific blade angle and can change slightly with ground speed.
In my op I said thrust, should be torque, sorry.
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Got a reference for that? All I can find supports my understanding...
https://www.skybrary.aero/index.php/Beta_Range
...as opposed to alpha range...
https://www.skybrary.aero/index.php/Alpha_Range
 
3393RP said:
In the early 80s I worked about a hundred yards from Mitsubishi's HOU hanger, which I believe was their national sales base. There were always six or eight aircraft with MA registration on hand.

Anyway, I loved it when the MU-2s would taxi past with the pilots moving beta to control speed. The huge amount of noise the TPE-331s and props made had me grinning almost every time.
Click to expand...

I'll admit that I wasn't a big fan at first of the noise. But now that my hearing has gotten worse, I do enjoy it. ;)

flyingron said:
MU-2's aren't pistons either.
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Well crap, I better go back and reread that POH. Obviously I missed something.
 
Ted DuPuis said:
I'll admit that I wasn't a big fan at first of the noise. But now that my hearing has gotten worse, I do enjoy it. ;)



Well crap, I better go back and reread that POH. Obviously I missed something.
Click to expand...

Subjectively I always thought the pt6 was louder in flight than the -10’s

They are only obnoxious on the ground.
 
Tarheelpilot said:
Subjectively I always thought the pt6 was louder in flight than the -10’s

They are only obnoxious on the ground.
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I agree with you on that. The high frequency noise that comes out of the intake is generally well muffled by the cabin and not entirely direct. Compare that to the low frequency noise coming out of the PT-6's exhaust directly at the cabin, it makes sense. The TPE-331 exhaust on pretty much any of them is further back. I've actually never sat in back of a TPE-powered aircraft so I don't know how loud they are there.

With a good headset, either of them are fine in the plane. The MT props on the MU-2 claim an 8 dB noise reduction (cabin) during flight, which I would believe. The stock props are an old Hartzell design that I would expect to be fairly noisy.
 
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