Aces High Bulletin Board
General Forums => The O' Club => Topic started by: Tigger29 on March 18, 2011, 04:17:55 PM
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http://www.youtube.com/watch?v=lQyGd6F2SKI (http://www.youtube.com/watch?v=lQyGd6F2SKI)
The short takeoff distance is absolutely incredible, but the best part of the video is at 1:16
How about that?
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I got .5 Hours logged in it :D
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I got .5 Hours logged in it :D
Hah, nice. They're always fun to watch at air show demeonstrations too, I believe they're one of a few aircraft capable of reversing (thrust) on the ground on its own power, and it's fun to watch them demonstrate it (as well as using it to rapidly decelerate on landing) at the shows. I always wonder what it must be like to be onboard something that big doing a maneuver like that unrestricted climb or some of the others they demonstrate at the airshows, you know it's just gotta feel different than anything else like it.
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Hah, nice. They're always fun to watch at air show demeonstrations too, I believe they're one of a few aircraft capable of reversing (thrust) on the ground on its own power, and it's fun to watch them demonstrate it (as well as using it to rapidly decelerate on landing) at the shows. I always wonder what it must be like to be onboard something that big doing a maneuver like that unrestricted climb or some of the others they demonstrate at the airshows, you know it's just gotta feel different than anything else like it.
can't a lot of airliners reverse thrust?
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can't a lot of airliners reverse thrust?
I believe not strong/capable enough to actualy reverse their planes on the ground (just to slow their forward speed down), but some may be able to but just can't because of safety or regs.
Also, here's a clip from the YouTube on a C-17 air show demo from NAF El Centro 2010 (I wasn't there last year, but wish I could of been).
http://www.youtube.com/watch?v=ooQJF1L__l8
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Hah, nice. They're always fun to watch at air show demeonstrations too, I believe they're one of a few aircraft capable of reversing (thrust) on the ground on its own power, and it's fun to watch them demonstrate it (as well as using it to rapidly decelerate on landing) at the shows. I always wonder what it must be like to be onboard something that big doing a maneuver like that unrestricted climb or some of the others they demonstrate at the airshows, you know it's just gotta feel different than anything else like it.
There are a number of airplanes that can do it on the ground. But the C-17 can do reverse thrust in the air. That way if you have to land somewhere in the enemy territory you don't have to be slow and low, you approach the airport at high altitude and do a diving final (What ever speeds I knew before I don't remember so I wont be able to give you numbers).
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Also, here's a clip from the YouTube on a C-17 air show demo from NAF El Centro 2010 (I wasn't there last year, but wish I could of been).
http://www.youtube.com/watch?v=ooQJF1L__l8
Awesome video! But sometimes I really do wish those announcers would receive lessons on the value of keeping their trap shut for more than 10 seconds at a time!
There are a number of airplanes that can do it on the ground. But the C-17 can do reverse thrust in the air. That way if you have to land somewhere in the enemy territory you don't have to be slow and low, you approach the airport at high altitude and do a diving final (What ever speeds I knew before I don't remember so I wont be able to give you numbers).
I've heard that it can maintain a 4500 metre/min descent rate like that :)
Interestingly enough, you can also do that in AH with a B-25 in a prolonged snap roll :D
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Also, here's a clip from the YouTube on a C-17 air show demo from NAF El Centro 2010 (I wasn't there last year, but wish I could of been).
http://www.youtube.com/watch?v=ooQJF1L__l8
"We don't have cables and rods, and pullys in that aircraft like your cessna." :aok
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I've heard that it can maintain a 4500 metre/min descent rate like that :)
Interestingly enough, you can also do that in AH with a B-25 in a prolonged snap roll :D
4500 meters/min or 4500 ft/min?
If it's feet than it's nothing really special.
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4500 meters/min or 4500 ft/min?
If it's feet than it's nothing really special.
Metres, I'm trying to convert myself to metric ;)
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Metres, I'm trying to convert myself to metric ;)
That's almost 15,000ft/min. Sounds about right.
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Airliners aren't allowed to reverse on own power, there was an incident where one reversed -> exhaust built up ice to wings and crashed fatally.
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Airliners aren't allowed to reverse on own power, there was an incident where one reversed -> exhaust built up ice to wings and crashed fatally.
I thought that depended on the specific airline?
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There are a number of airplanes that can do it on the ground. But the C-17 can do reverse thrust in the air. That way if you have to land somewhere in the enemy territory you don't have to be slow and low, you approach the airport at high altitude and do a diving final (What ever speeds I knew before I don't remember so I wont be able to give you numbers).
Ah, thank you for the correction, I knew it had something unique with its reverse thrust, just forgot the particulars. Still, it's the only plane I know of to of demonstrated it regularly at the airshows on the ground (and to think of it, may be the only plane I've seen/witnessed reverse on its own power on the ground, ever in my life).
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Awesome video! But sometimes I really do wish those announcers would receive lessons on the value of keeping their trap shut for more than 10 seconds at a time!
I've heard that it can maintain a 4500 metre/min descent rate like that :)
Interestingly enough, you can also do that in AH with a B-25 in a prolonged snap roll :D
:D I've contemplating finding the power or main feed comming out of the anouncer area and pulling it conveniently just at the right time to enjoy my favorite performance, but I figure the world we live in these days it could land me in jail for a night or two on suspicion of commiting an act of terrorism/un-patriotism.
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:D I've contemplating finding the power or main feed comming out of the anouncer area and pulling it conveniently just at the right time to enjoy my favorite performance, but I figure the world we live in these days it could land me in jail for a night or two on suspicion of commiting an act of terrorism/un-patriotism.
I know what you mean but it's their job to keep talking and make sure your not bored and know what's going on. Imagine an airshow without anyone talking.
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I know what you mean but it's their job to keep talking and make sure your not bored and know what's going on. Imagine an airshow without anyone talking.
I used to think that until one day when I was at Duxford, and an announcer was talking over a Spitfire taking off...NO ONE talks over Spitfires.
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I used to think that until one day when I was at Duxford, and an announcer was talking over a Spitfire taking off...NO ONE talks over Spitfires.
True :furious
I take back what I said.
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There are a number of airplanes that can do it on the ground. But the C-17 can do reverse thrust in the air. That way if you have to land somewhere in the enemy territory you don't have to be slow and low, you approach the airport at high altitude and do a diving final (What ever speeds I knew before I don't remember so I wont be able to give you numbers).
have any info on the system they use for this?
Airliners can still reverse out of gates with their own engines if the plane can physically do it, however its typically not done unless its the only option. DC-9/MD-80's are known for doing them, the 732's used to (it was an Air Florida 732 that crashed due to icing from doing it), and a few others could. Ive heard from people that lightly loaded 737 classics and NGs along with A32x's can do them as well. The 777 deffinately has the power to do them, though i wouldnt know why you would want to with a plane that big. The 777 is another high performer like the C-17. Some pretty interesting takeoffs in them when lightly loaded.
Its called an assualt landing. We do them in our C-123k every now and then when we arrive at airshows, just depends on whos flying it. Come in relatively fast and level, chop power and dive for the runway.
babalonian, have you never seen the blue angels perform? Fat Albert backs up during every show.
The c17 is an amazing plane. how many other planes can land on a 3500ft dirt strip fully loaded and then take back off still fully loaded?
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Airliners can still reverse out of gates with their own engines if the plane can physically do it, however its typically not done unless its the only option. DC-9/MD-80's are known for doing them, the 732's used to (it was an Air Florida 732 that crashed due to icing from doing it), and a few others could. Ive heard from people that lightly loaded 737 classics and NGs along with A32x's can do them as well. The 777 deffinately has the power to do them, though i wouldnt know why you would want to with a plane that big.
The big reason they dont use reverse is FOD, plus a multitude of lesser reasons not to use it.
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have any info on the system they use for this?
I do not have any official info on the specific systems used in C-17, sorry.
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How much thrust can a jet engine supply when in reverse? Is it anywhere near what its maximum power is?
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It'll go all the way to eleven if you don't stop it. Depending on how the engine is controlled which these days is either a DEEC or a FADEC system that allows a simpler operation from a pilots standpoint. They keep the engines from overspeeding, overtemping, flaming out, compressor stalls, synced with each other and a laundry list of other functions. When reverse is selected either by lifting some paddles on the thrust levers or selecting reverse by unlocking the levers over a mechanical stop depending on the aircraft the computers use several systems to determine the next course of action. Usually weight on wheels is required for the TRs to deploy however that's not the case for all airplanes some of which don't others need to have wheel spinup criteria met before allowing them to deploy. Once whatever criteria are met to allow the TRs themselves to deploy the clamshell doors (ex. DC9, MD80) or the cascade (ex B737-300 and newer, A320, B777) will open. Once deployed the engine spins up and the exhaust or bypass air is redirected a direction other than backward. Some is directed forward, some sideways and still some isn't redirected depending on the system. Once deployed the engine controllers or computers limit the thrust produced to whatever the limit is for the engine. Other airplanes require manual actuation not to exceed a certain power setting based on rotation speed of the turbines or an internal pressure (EPR).
The engines themselves don't swap directions of rotations but rather redirect the airflow.
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Interesting stuff, thanks!