Moderators: richierich, ua900, PanAm_DC10, hOMSaR

 
konrad
Topic Author
Posts: 584
Joined: Fri Mar 15, 2002 3:54 am

ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 4:19 pm

Yesterday, sitting on an Air Dolomiti ATR 72 in Munich I was witness to the ATR on neighboring stand backing away from the stand under its own power, reversing and continuing to taxi to the runway. A moment later the ATR I was on did the same trick. There was no push-back truck involved.

Would anyone care to explain how is this done? I didn't think the propellers can turn in the opposite direction?
 
UTA_flyinghigh
Posts: 6304
Joined: Wed Oct 03, 2001 8:46 pm

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 4:33 pm

The propellers do not turn in the opposite direction but the blades rotate in order to achieve the same effect. The same principle is used for lanfing which produces the same effect as reverse thrust on jet engines.

It is SOP at AZ tu use this for pushack on their AT7's.

UTA  checkeredflag 
Fly to live, live to fly - Air France/KLM Flying Blue Platinum, BMI Diamond Club Gold, Emirates Skywards
 
kstatepilot
Posts: 114
Joined: Wed Mar 21, 2007 9:23 am

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 4:47 pm

I know that the when I used to fly the Shorts for 2Q here in the states it was commonplace for us to back the airplane up using prop reverse. Even did it without guide men quite a bit.

I have also seen King Airs do it, and MD-80's. I do think that it isn't commonplace but can happen.
 
cirrusdriver
Posts: 115
Joined: Thu Nov 23, 2006 1:29 pm

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 4:51 pm

NW used to do that in MSP from the gate area when the snow was to deep for the push back tractors.
 
konrad
Topic Author
Posts: 584
Joined: Fri Mar 15, 2002 3:54 am

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 4:56 pm



Quoting UTA_flyinghigh (Reply 1):
The propellers do not turn in the opposite direction but the blades rotate in order to achieve the same effect. The same principle is used for lanfing which produces the same effect as reverse thrust on jet engines.

Thanks, nice to know how this happens. Is this used for "reverse thrust" braking as well ? And can Dash 8's do it ?
 
kstatepilot
Posts: 114
Joined: Wed Mar 21, 2007 9:23 am

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 5:26 pm



Quoting Konrad (Reply 4):
Thanks, nice to know how this happens. Is this used for "reverse thrust" braking as well ? And can Dash 8's do it ?

I believe all common turbo-prop engines can do this.
 
PiedmontINT
Posts: 220
Joined: Sun Jul 10, 2005 8:12 am

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 5:42 pm

I knew rear engined jets like DC-9s, MD-80s, etc. could "power back" and push back on their own power but I haven't seen a turboprop do this.. Anyone have a link to a video of a prop doing this? Whats the smallest turboprop that can do this?
 
sandrozrh
Posts: 2419
Joined: Sun Feb 04, 2007 12:19 am

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 5:52 pm

It's common practice with the ATRs, I myself witnessed it at various airports. Just three weeks ago i saw an Aero Airlines/finnair ATR42 do it at TLL.
 
alespesl
Posts: 562
Joined: Mon Jan 19, 2004 7:59 am

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 6:05 pm

Here in PRG all Czech Airlines ATRs do this on daily basis. It is a very common practice and good feature for this a/c.
 
OV735
Posts: 832
Joined: Sat Jan 17, 2004 8:49 am

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 6:07 pm



Quoting Konrad (Reply 4):
And can Dash 8's do it ?

Theoretically it should be possible with any turboprop, however as far as I've noticed at TLL, only the ATRs and Fokker 50's do that. The SK Dash 8's we used to have were always pushed back with the tug. No idea, why. Might be just SAS company procedure.
 
User avatar
N14AZ
Posts: 4137
Joined: Sat Feb 24, 2007 10:19 pm

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 6:32 pm

Similiar topic was discussed some months ago about TAROM's ATRs: Pushback On ATRs (by FlyMeToTheMoon Jun 26 2007 in Civil Aviation)
 
copter808
Posts: 1384
Joined: Sat Dec 30, 2000 1:14 pm

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 6:52 pm



Quoting PiedmontINT (Reply 6):
I knew rear engined jets like DC-9s, MD-80s, etc. could "power back" and push back on their own power but I haven't seen a turboprop do this.. Anyone have a link to a video of a prop doing this? Whats the smallest turboprop that can do this?

Most any jet with thrust reversers can do it, however it's generally not done with wing mounted engines because of FOD (Foreign Object Damage) concerns. Tail mounted engines are usually higher above the ground.

Any airplane with a reversible pitch prop can back up. It has nothing to do with the size of the aircraft, or even whether it's turbine powered.
 
N766UA
Posts: 8314
Joined: Thu Jul 29, 1999 3:50 am

RE: ATR Backing Away Out Of Parking Position

Thu Nov 29, 2007 6:54 pm

It's alot more common for props, as there isn't the same risk of ingesting FOD with full reverse as there is on jets. The props spin normally, but the pitch of the blades is adjusted so as to produce reverse thrust. The only difference is the way the wind's blowing, and the noise!
 
avt007
Posts: 1989
Joined: Mon Jul 10, 2000 4:51 am

RE: ATR Backing Away Out Of Parking Position

Fri Nov 30, 2007 3:00 am

I have done it in a Shorts 360, and Dash8s. The risk on both aircraft is that they have trailing link nose gears, which want to caster around, and rip the gear off. You have to be very careful indeed, and never use the brakes to stop. Doing so can tip you over on your tail. Otherwise it's not a big deal for a turboprop. Incidentally, the Dash is limited on how long use can use full reverse thrust, since the airflow is no longer flowing through the oil cooler.
 
Dakar
Posts: 70
Joined: Wed Nov 16, 2005 5:11 am

RE: ATR Backing Away Out Of Parking Position

Fri Nov 30, 2007 5:34 am

I wonder how much thrust is produced in reverse? Obviously enough to get to breakaway speed and roll but the blades aren't symmetrical and the tips are aerodynamically shaped, correct?

That has to be one reason they are so noisy.

Nick
 
2H4
Posts: 7960
Joined: Tue Oct 19, 2004 11:11 pm

RE: ATR Backing Away Out Of Parking Position

Fri Nov 30, 2007 5:49 am

Turboprop:






Turbojet:




2H4
Intentionally Left Blank
 
User avatar
tb727
Posts: 2204
Joined: Thu Jun 30, 2005 1:40 pm

RE: ATR Backing Away Out Of Parking Position

Fri Nov 30, 2007 5:59 am

Yeah, I've done it in the MU2, man those things are noisy already. It's ok, you just have to remember not to touch the brakes! I've always wanted to do it in the Lear 25 but I never did, mostly because you aren't supposed to in them. Plus those are noisy enough already too. You'll notice in the NW DC-9 video, it moved forward, they roll forward to make sure the brakes are released. I have never seen or heard of a commuter sized Turboprop doing it, cool.
Too lazy to work, too scared to steal!
 
User avatar
HAWK21M
Posts: 30067
Joined: Fri Jan 05, 2001 10:05 pm

RE: ATR Backing Away Out Of Parking Position

Fri Nov 30, 2007 10:36 am

very Interesting links.

How would a Powerback usage damage a Turboprop in the long run.As would a Turbofan.
If there is a shortage of towtrucks why not.

regds
MEL
I may not win often, but I damn well never lose!!! ;)
 
boeing767mech
Posts: 806
Joined: Fri Dec 15, 2000 5:03 pm

RE: ATR Backing Away Out Of Parking Position

Fri Nov 30, 2007 11:52 pm

Here is a video from Flightlevel 350 of a C-17 backing up and turning onto another taxi way.

http://www.flightlevel350.com/Aircra...Air_Force_Aviation_Video-3327.html

David
Never under-estimate the predictably of stupidty
 
Viscount724
Posts: 19316
Joined: Thu Oct 12, 2006 7:32 pm

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 3:03 am

This video of C-130 test landings/takeoffs on an aircraft carrier in 1963 includes brief footage of it backing into takeoff position under its own power.
http://www.youtube.com/watch?v=CfwJJD5jGXk
 
soon7x7
Posts: 2267
Joined: Thu May 04, 2006 10:51 am

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 3:37 am

Fly American to Dallas and then leave on an American MD-80, they'll do the same thing...why?...cause they can...j
 
TEBGuy
Posts: 237
Joined: Thu Feb 03, 2005 6:26 am

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 4:30 am



Quoting HAWK21M (Reply 17):
very Interesting links.

How would a Powerback usage damage a Turboprop in the long run?

As Avt007 said:

Quoting Avt007 (Reply 13):
Incidentally, the Dash is limited on how long use can use full reverse thrust, since the airflow is no longer flowing through the oil cooler.

Since a turboprop reverses the pitch of the blades to apply reverse thrust, it basically blows air from back to front. In normal operation, air would be moving front to back, cooling vital engine bits. Said bits will not be in the stream of air created by the prop when in reverse pitch. At least, that's my understanding of it.
Remember, taking off is optional, landing is mandatory.
 
User avatar
Starlionblue
Posts: 19926
Joined: Fri Feb 27, 2004 9:54 pm

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 5:30 am



Quoting PiedmontINT (Reply 6):
I knew rear engined jets like DC-9s, MD-80s, etc. could "power back" and push back on their own power but I haven't seen a turboprop do this.. Anyone have a link to a video of a prop doing this? Whats the smallest turboprop that can do this?

It's not quite the same thing. Turbojets/turbofans powerback using reversers., Turboprops do it using reverse pitch. The former is much more stressful on the engine and carries a FOD risk.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
stratosphere
Posts: 1770
Joined: Sat Sep 22, 2007 12:45 pm

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 5:57 am



Quoting Tb727 (Reply 16):
You'll notice in the NW DC-9 video, it moved forward, they roll forward to make sure the brakes are released

Actually they move forward to get off the flat spot on the tires after sitting at the gate. Is less stressful on the engines. I have also seen 757's do powerbacks. Eastern used to do it at EWR when I used to work there. But I have never seen any other carrier powerback anything larger than a 727.
 
User avatar
HAWK21M
Posts: 30067
Joined: Fri Jan 05, 2001 10:05 pm

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 7:41 am



Quoting Stratosphere (Reply 23):
I have also seen 757's do powerbacks.

what powerplant would that be the RRs or P&Ws.
regds
MEL
I may not win often, but I damn well never lose!!! ;)
 
stratosphere
Posts: 1770
Joined: Sat Sep 22, 2007 12:45 pm

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 4:06 pm



Quoting HAWK21M (Reply 24):
what powerplant would that be the RRs or P&Ws.
regds
MEL

Eastern airlines had the Rolls powered engine.
 
avt007
Posts: 1989
Joined: Mon Jul 10, 2000 4:51 am

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 6:06 pm



Quoting TEBguy (Reply 21):
Since a turboprop reverses the pitch of the blades to apply reverse thrust, it basically blows air from back to front. In normal operation, air would be moving front to back, cooling vital engine bits. Said bits will not be in the stream of air created by the prop when in reverse pitch. At least, that's my understanding of it.

You understand correctly, but the sidenote I added about time limits is for full power reverse checks. Yuo don't want to exceed 5 minutes, IIRC. So a power back is not a problem. The biggest risk is damaging the nose gear, or tipping over, hitting something behind you.
 
MQTmxguy
Posts: 129
Joined: Sun Nov 11, 2007 3:58 pm

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 7:39 pm

I've seen BE1s do it as well
Well at least we can all take comfort in the fact that NW will never retire their DC-9s
 
User avatar
HAWK21M
Posts: 30067
Joined: Fri Jan 05, 2001 10:05 pm

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 8:31 pm



Quoting Stratosphere (Reply 25):
Eastern airlines had the Rolls powered engine

Thanks.I presume the -E4s.
regds
MEL
I may not win often, but I damn well never lose!!! ;)
 
boeing767mech
Posts: 806
Joined: Fri Dec 15, 2000 5:03 pm

RE: ATR Backing Away Out Of Parking Position

Sat Dec 01, 2007 11:51 pm



Quoting HAWK21M (Reply 28):


Quoting Stratosphere (Reply 25):
Eastern airlines had the Rolls powered engine

Thanks.I presume the -E4s.
regds
MEL

Eastern had R211-535C's and 535E's

David
Never under-estimate the predictably of stupidty
 
jman40
Posts: 59
Joined: Sun Aug 13, 2006 3:50 am

RE: ATR Backing Away Out Of Parking Position

Tue Dec 04, 2007 3:36 am



Quoting Soon7x7 (Reply 20):
Fly American to Dallas and then leave on an American MD-80, they'll do the same thing...why?...cause they can...j

Sadly, I don't think they're doing this anymore. I go through DFW 10-15 times per year (always on MD80s, it seems), and I don't remember the last powerback I experienced. Maybe I'm just not lucky.
 
johnclipper
Posts: 537
Joined: Thu Aug 25, 2005 5:44 am

RE: ATR Backing Away Out Of Parking Position

Wed Dec 05, 2007 9:21 am

I've been on an EA 757 at ATL doing a power pushback. The spoliers automatically came up when reverse was applied.
"Flown every aircraft since the Wright Flyer" (guys, if you take this literally, then you need to get a life...)
 
User avatar
HAWK21M
Posts: 30067
Joined: Fri Jan 05, 2001 10:05 pm

RE: ATR Backing Away Out Of Parking Position

Wed Dec 05, 2007 9:31 am



Quoting Boeing767mech (Reply 29):
Eastern had R211-535C's and 535E's

Do they still have the -535Cs.

Quoting JohnClipper (Reply 31):
The spoliers automatically came up when reverse was applied.

You sure it was automatic.

regds
MEL
I may not win often, but I damn well never lose!!! ;)
 
boeing767mech
Posts: 806
Joined: Fri Dec 15, 2000 5:03 pm

RE: ATR Backing Away Out Of Parking Position

Wed Dec 05, 2007 11:19 am



Quoting HAWK21M (Reply 32):


Quoting Boeing767mech (Reply 29):
Eastern had R211-535C's and 535E's

Do they still have the -535Cs.

Quoting JohnClipper (Reply 31):
The spoliers automatically came up when reverse was applied.

You sure it was automatic.

regds
MEL

Eastern has been out of business for at least 15 years so no they don't have 535C's anymore, The spoiler will deploy if they where in the armed position.

David
Never under-estimate the predictably of stupidty
 
Tristarsteve
Posts: 3663
Joined: Tue Nov 22, 2005 11:04 pm

RE: ATR Backing Away Out Of Parking Position

Wed Dec 05, 2007 12:39 pm



Quoting Boeing767mech (Reply 33):
The spoiler will deploy if they where in the armed position.

The spoilers don't have to be armed to deploy. Just selecting reverse thrust levers will deploy the spoilers. There is a mechanical connection between the reverse thrust lever and the spoiler handle. A little cam knocks the spoiler handle up into the arm position. It is there for auto spoilers on a rejected take off.
 
boeing767mech
Posts: 806
Joined: Fri Dec 15, 2000 5:03 pm

RE: ATR Backing Away Out Of Parking Position

Wed Dec 05, 2007 12:44 pm



Quoting TristarSteve (Reply 34):
The spoiler will deploy if they where in the armed position.

The spoilers don't have to be armed to deploy. Just selecting reverse thrust levers will deploy the spoilers. There is a mechanical connection between the reverse thrust lever and the spoiler handle. A little cam knocks the spoiler handle up into the arm position. It is there for auto spoilers on a rejected take off.

Your right I stand corrected, the joy of working on 7 different fleet types and not having sleep in 28 hours, they all run together.

David
Never under-estimate the predictably of stupidty
 
Tristarsteve
Posts: 3663
Joined: Tue Nov 22, 2005 11:04 pm

RE: ATR Backing Away Out Of Parking Position

Wed Dec 05, 2007 12:45 pm

Talking of powerback, when I worked in the GF hangar in BAH, GF operated 4 Skyvans. When they came up to BAH for maint (they were based in MCT) the engineer used to back them into the hangar using reverse pitch. I can still visualise his head sticking out of the cockpit roof hatch as he backed in!
What a row they made. Garret constant speed props.
After the C Check they had to do a flight test for flight idle rate of descent check, to ensure that at flight idle the constant speed prop was not producing too much power. The pilot was always walking round the hangar trying, without success, to get a volunteer to go with him!
 
User avatar
HAWK21M
Posts: 30067
Joined: Fri Jan 05, 2001 10:05 pm

RE: ATR Backing Away Out Of Parking Position

Wed Dec 05, 2007 9:00 pm



Quoting Boeing767mech (Reply 33):
The spoiler will deploy if they where in the armed position.



Quoting TristarSteve (Reply 34):
Just selecting reverse thrust levers will deploy the spoilers. There is a mechanical connection between the reverse thrust lever and the spoiler handle

The Mechanical Cam on the R/T lever mvmt pushes the Speedbrake lever out of the detent & the Sw contacted selects the speedbrake actuator to move the lever aft.
Similiar to the B737s.

regds
MEL
I may not win often, but I damn well never lose!!! ;)

Who is online

Users browsing this forum: No registered users and 31 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos