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Postby osvep » Tue Feb 06, 2007 12:44 am

Costellations,DC4,6,7 have pitch reverser in their propellers(at least I red it).But models does not include this gadget .How real pilots use them?Must be in flying as in turbo props
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Re:  big

Postby Ivan » Tue Feb 06, 2007 2:41 am

[quote]Costellations,DC4,6,7 have pitch reverser in their propellers(at least I red it).But models does not include this gadget .How real pilots use them?Must be in flying as in turbo props
Russian planes: IL-76 (all standard length ones),  Tu-154 and Il-62, Tu-134 and [url=http://an24.uw.hu/]An-24RV[/ur
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Re:  big  piston planes how to use propp

Postby beaky » Tue Feb 06, 2007 4:22 pm

I don't think "beta" pitch was available in all real-life versions of the aircraft listed... the mighty Boeing 377 had it, but was much heavier than the others.
I've never had any trouble stopping 4-engine  propliners (except the Strat) in FS9 without beta pitch... it's not like they're intended for short strips!

As for ground ops, it's just not practical to use the engines for backing up: wasted fuel, flying debris, wear and tear on the engines, etc... the Boeing, for example, only used its reversible props for braking on the runway, it was not intended for use on the ramp.

Side note: I've never heard of beta pitch being used in flight intentionally, even with turbine engines, except in extreme emergencies.
Last edited by beaky on Tue Feb 06, 2007 4:25 pm, edited 1 time in total.
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Re:  big  piston planes how to use propp

Postby RitterKreuz » Tue Feb 06, 2007 11:16 pm

i heard about a SAAB 340 from some operator way back in the day - apparantly they were high on the approach and slightly fast, the fairly new captain lifted the power lever triggers and pulled the engines into beta to help slow down the speed.

as a result the props did weird aerodynamic things and went into an uncontrollable over speed. the prop RPM gages were pegged off the measurable scale of the gage and as a result the torque, Ng, and ITT also went way out of the envelope which resulted in complete destruction of the engines within a matter of seconds.

they landed the plane without any engine power and ran off the end of the runway... nobody was hurt but in response to this incident an automatic flight idle stop was installed on all saab 340s to prevent the levers from being moved below flight idle when there is no weight on the wheels.

I do know that there is a certain model of king air that can be pulled harmlessly into beta in flight, but pilots are advised against this because of the 1 in a million chance that the props STICK in beta in flight!

It is possible to back up a large aircraft on the ramp using the "reverse" on the props but the biggest risk in doing this is when you try to stop the aircraft is very likely to fall on its tail. part of the C90 training that i went through a couple of years ago focused on "power backs" they told us NEVER to do it... but if we HAD to here is how to do it without breaking anything.  ::)

in real life the reverse of the props is only used as an aide to breaking on the landing roll out, or to control speed during taxi, it is really not used in any other realm of flight.
Last edited by RitterKreuz on Tue Feb 06, 2007 11:18 pm, edited 1 time in total.
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Re:  big  piston planes how to use propp

Postby beaky » Wed Feb 07, 2007 12:35 am

i heard about a SAAB 340 from some operator way back in the day - apparantly they were high on the approach and slightly fast, the fairly new captain lifted the power lever triggers and pulled the engines into beta to help slow down the speed.

as a result the props did weird aerodynamic things and went into an uncontrollable over speed. the prop RPM gages were pegged off the measurable scale of the gage and as a result the torque, Ng, and ITT also went way out of the envelope which resulted in complete destruction of the engines within a matter of seconds.

they landed the plane without any engine power and ran off the end of the runway... nobody was hurt but in response to this incident an automatic flight idle stop was installed on all saab 340s to prevent the levers from being moved below flight idle when there is no weight on the wheels.

I do know that there is a certain model of king air that can be pulled harmlessly into beta in flight, but pilots are advised against this because of the 1 in a million chance that the props STICK in beta in flight!

It is possible to back up a large aircraft on the ramp using the "reverse" on the props but the biggest risk in doing this is when you try to stop the aircraft is very likely to fall on its tail. part of the C90 training that i went through a couple of years ago focused on "power backs" they told us NEVER to do it... but if we HAD to here is how to do it without breaking anything.  ::)

in real life the reverse of the props is only used as an aide to breaking on the landing roll out, or to control speed during taxi, it is really not used in any other realm of flight.


I am vindicated... ;D

As little as I know about constant-speed props, I know this much: if you have to go into beta in flight , you've already screwed up.
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Re:  big  piston planes how to use propp

Postby RitterKreuz » Wed Feb 07, 2007 1:35 am

you've got that right Rotty

i'll say this much - even if i was flying a plane where beta was allowed in flight, i would be VERY hesitant to use it even once.
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Re:  big

Postby Ivan » Wed Feb 07, 2007 3:01 am

Tu-95 sometimes uses Beta range inflight.
Tu-154M (not sure about the B) and Il-62 always use reversers just before touchdown
DC-8 and DH Trident could use reversers inflight. Trident for highspeed descent, and DC-8 because it doesnt have airbrakes
Russian planes: IL-76 (all standard length ones),  Tu-154 and Il-62, Tu-134 and [url=http://an24.uw.hu/]An-24RV[/ur
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Re:  big  piston planes how to use propp

Postby RitterKreuz » Wed Feb 07, 2007 3:36 am

seems like i have heard of turbine powered air tractors (crop dusters) using beta as they cross the numbers.
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Re:  big  piston planes how to use propp

Postby expat » Wed Feb 07, 2007 5:50 am

To change track slightly, the C17 Globe Master can use thrust reverse in flight for tactical drops enabling I believe a descent rate of up 20000 feet per minute  be produced. I would like to see it, but not be on board.

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Re:

Postby Ivan » Wed Feb 07, 2007 9:10 am

[quote]To change track slightly, the C17 Globe Master can use thrust reverse in flight for tactical drops enabling I believe a descent rate of up 20000 feet per minute
Russian planes: IL-76 (all standard length ones),  Tu-154 and Il-62, Tu-134 and [url=http://an24.uw.hu/]An-24RV[/ur
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Re:  big  piston planes how to use propp

Postby expat » Wed Feb 07, 2007 11:19 am

To change track slightly, the C17 Globe Master can use thrust reverse in flight for tactical drops enabling I believe a descent rate of up 20000 feet per minute  be produced. I would like to see it, but not be on board.

Matt

There is a video of that on flightlevel350


The video shots of Shuttle cockpit re-entry seem to produce less vibration :o

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2. And, if you have time to write the fault on a napkin and attach to it to the yoke.........you have time to write it in the tech log....see point 1.
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Re:  big  piston planes how to use propp

Postby elite marksman » Fri Feb 23, 2007 5:50 pm

I believe that the C-130 can also throw its props into full reverse before landing. However, this is only used in emergencies and very short strips.
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Re:  big

Postby DaveSims » Thu Mar 15, 2007 9:07 pm

The PC-6 Porter can reverse in flight, its how they race skydivers to the ground, point it straight down and throw it in reverse.  Few if any piston engine planes have reverse, though.  

As for backing up a C90, just watched a guy do it yesterday trying to get turned around in a tight spot.  Definitely a different maneuver to see.  
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Re:  big

Postby FLYING_TRUCKER » Thu May 31, 2007 9:01 pm

Hi all  ;)

I have watched the military C17s and the C130s back up on the ramp into their parking spots many many times.
The Twin Otter, Aurora and Buffalo are other aircraft I have watched back up many times.

There are days I wish my bugsmashers could back up and wash themselves as well.   ;D

Cheers...Happy Landings...Doug
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