Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: artik on June 09, 2014, 09:34:38 AM
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What are these guys doing?
(http://www.c4militarynews.com/wp-content/uploads/2013/09/130909-F-LP948-001.jpg)
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Looking for a needle on the runway maybe?
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Looking for a needle on the runway maybe?
Pretty much. They walk the runway and flight deck before ops to pick up and remove any debris that could cause damage to an engine.
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I find that funny yet seriously important. :old:
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indeed. Quite the SOP on aircraft carries and air bases. Anything can can get sucked up in to an engine or cause damage to a tire. Anything.
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I've always believed it was a major weakness in western combat jets. If WWIII had happened every concrete runway in the world would have been cratered in short order. All combat aircraft should be able to operate from rough airfields. That a multimillion Dollar jet can be ruined by a piece of debris so small that people have to walk the runway to look for it is completely ridiculous.
(https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcRe_fSPyBiALhk7H3k9wbBhvejxJujskMfYSeIeMNRHHCELqc0I)
(http://www.bibliotecapleyades.net/imagenes_sociopol/iran21_01.jpg)
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It's called the FOD Walk or foreign object damage. I've done it on occasion on the LHAs. Someone yells down to the berthing area "turn out for fahd walk!" Sometimes over emphasizing the faaaaaaaaaaaaahd waaaaaaaaaaalk. very annoying.
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I've always believed it was a major weakness in western combat jets. If WWIII had happened every concrete runway in the world would have been cratered in short order. All combat aircraft should be able to operate from rough airfields. That a multimillion Dollar jet can be ruined by a piece of debris so small that people have to walk the runway to look for it is completely ridiculous.
(https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcRe_fSPyBiALhk7H3k9wbBhvejxJujskMfYSeIeMNRHHCELqc0I)
(http://www.bibliotecapleyades.net/imagenes_sociopol/iran21_01.jpg)
I love Russian equipment! I am Russian! :old:
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I remember sweepers but never having seen airmen actually walk the runways.
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What are these guys doing?
Serving in the US armed forces?
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I've always believed it was a major weakness in western combat jets. If WWIII had happened every concrete runway in the world would have been cratered in short order. All combat aircraft should be able to operate from rough airfields. That a multimillion Dollar jet can be ruined by a piece of debris so small that people have to walk the runway to look for it is completely ridiculous.
(https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcRe_fSPyBiALhk7H3k9wbBhvejxJujskMfYSeIeMNRHHCELqc0I)
(http://www.bibliotecapleyades.net/imagenes_sociopol/iran21_01.jpg)
I don't see anything blocking the intakes on those jets to make them less vulnerable than western jets.
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It's called the FOD Walk or foreign object damage. I've done it on occasion on the LHAs. Someone yells down to the berthing area "turn out for fahd walk!" Sometimes over emphasizing the faaaaaaaaaaaaahd waaaaaaaaaaalk. very annoying.
Finally - somebody called the name FOD Walk. Also in general you are correct.
About Russian jets - the Su-27 and MiG-29 (old ones) have the "FOD Screen" but in general they are dropping them like in MiG-35 and MiG-29M or their stealth Suchoi. In general the Russian engines are more prone to FOD, also another problem rather the Russian runways that in generally has lower quality maintenance.
About runways being destroyed - if it is destroyed the FOD is the "lesser" problem - first you need to close the holes. And today everybody does this efficiently (everybody learned the 1967 6 Day War lessons)
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I remember sweepers but never having seen airmen actually walk the runways.
Yeah you're right, we usually only did the flightline. They had sweepers for the runway and taxiways.. One time I remember us actually walking the runway, but that was looking for a missing part from an aircraft that lost a tire
on takeoff.
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I don't see anything blocking the intakes on those jets to make them less vulnerable than western jets.
Look closer.
(http://theaviationist.com/wp-content/uploads/2013/03/Polish-Mig-29.jpg)
I love that Polish paint scheme... Especially with the WWII heroes they honor on the tail.
In T/O and landing config the engines draw air from the gills on the upper surface of the LERX. Internal doors close the main intakes. The Su-25 doesn't need any since it sits so high off the ground in a nose-up attitude.
(http://webspace.webring.com/people/rj/jica-aas/su25_frogfoot.jpg)
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Here's a Russian regional airliner taking off from a typical Russian regional airport...
https://www.youtube.com/watch?v=BZbF2OrNkhE
:uhoh
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Look closer.
(http://theaviationist.com/wp-content/uploads/2013/03/Polish-Mig-29.jpg)
I love that Polish paint scheme... Especially with the WWII heroes they honor on the tail.
In T/O and landing config the engines draw air from the gills on the upper surface of the LERX. Internal doors close the main intakes. The Su-25 doesn't need any since it sits so high off the ground in a nose-up attitude.
(http://webspace.webring.com/people/rj/jica-aas/su25_frogfoot.jpg)
I want a Frogfoot! :old: What are they selling for these days?
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I've heard about a privately owned SU-25, but I've never seen it, and I have no idea what something like that would cost. Lots of decadent imperialist capitalist money for sure! :confused:
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Look closer.
(http://theaviationist.com/wp-content/uploads/2013/03/Polish-Mig-29.jpg)
I love that Polish paint scheme... Especially with the WWII heroes they honor on the tail.
In T/O and landing config the engines draw air from the gills on the upper surface of the LERX. Internal doors close the main intakes. The Su-25 doesn't need any since it sits so high off the ground in a nose-up attitude.
What your picture shows is the original solution for MiG 29, but as already stated, they changed it in later models to retractable grids in order to use the space inside the LERX for more fuel:
http://forum.keypublishing.com/showthread.php?53622-Su-27-3x-vs-Mig-29-Take-off-amp-landing-from-Unpaved-Rough-field&s=2e717145d60bff855c429b9305fa5f9c&p=847660#post847660
Similar to Su-27's:
http://www.arcforums.com/forums/air/index.php?showtopic=199152&view=findpost&p=1877412
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Until you've done a FOD walk-down on GTMO's ramp, you haven't done one yet. We'd collect at least a dozen land crabs every morning... The occasional Iguana too....
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Those were developed for the naval version of the MiG-29 the K-model. They only needed to stop it from inhaling deck crewmen and their back-pocket spanners! ;) Unlike the MiG-29 the Su-27 is not a "front line fighter" and wasn't expected to operate from rough unprepared runways. Its primary mission was/is to defend the Soviet Union/Russia from strategic bombers. However, still the Su-27 has a highly effective protection against ingesting foreign objects.
(http://static.rcgroups.net/forums/attachments/2/7/0/6/9/4/a5647374-146-SU27%20FOD%20screen.jpg?d=1364319679)
Anything that gets through that screen won't be big enough to cause any problems.
Except for the original MiG-29M all the modernized versions also have the gills, like this MiG-29SMT:
(https://dl.dropboxusercontent.com/u/26232318/MiG-29SMT.JPG)
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This info came from a Russian pilot. He said the FOD screens on the Mig-29 did not work as intended. Since they retract, anything on the screens will just get sucked into the engine when retracting.
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What MiG did he fly? The 29K? On the land based 29s there are no screens. There are doors.
(https://dl.dropboxusercontent.com/u/26232318/AH/mig29front.JPG)
(https://dl.dropboxusercontent.com/u/26232318/AH/mig29intake.JPG)
I can't see how any FOD would get stuck on those doors unless you somehow spray them with mud. There can't be enough airflow to suck anything up from the ground.
The screens on the Su-27, in my previous post, retract downward trapping the FOD underneath them.
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Except for the original MiG-29M all the modernized versions also have the gills, like this MiG-29SMT:
If I'm not mistaken, the MiG-29SMT is an upgrade designed around the early airframe, so it can be retrofited to existing MiG-29s. It was an attempt to give old 29s capabilities similar to the MiG-29M. From what I have read, there is a further development around it, the SMT-2, that dispenses with the louvers.
The MiG-29M has been the basis for the "latest and greatest" development, the MiG-35 (so devoid of louvers too). You get a glimpse of the grids of the engines in this video at 0:20. It's the best that I could find!
http://youtu.be/zDfmfp4dUrc?t=20s
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Yes, all the upgrades for the MiG-29 are just that... Upgrades. I've never heard of the SMT-2, but the MiG-35 seems to be an upgraded 29M. Mikoyan must need more export money to develop the LMFS! ;)
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On top of all this, it was discovered that the unique FOD doors on the MiG-29's inlets were not stopping material from getting into the engine ducts. Since the doors retracted "up" into the inlet, debris that was kicked up by the nose wheel lodged on or at the bottom of the door seal and then was ingested into the engine when the door opened during the nose gear lifted off the ground during takeoff.
This problem was known from the earliest days. After the first four MiG-29 prototypes were evaluated, the nose gear was moved further back, but nose wheel "mud-flaps" or guards were still required to protect the engine from flying debris. It took until 1988 before all delivered aircraft were so equipped, therefore the initial batch of InAF aircraft had to be locally retro-fitted with mud guards and that activity was not completed until June 1992. All costs were supposed to be re-imbursed by the contractor but Mikoyan reneged and left the InAF with $300,000 in liabilities. In subsequent MiG-29K/M models the FOD doors were replaced by screens that closed "down", forcing any debris out of the louvers repositioned to the lower side of the inlet duct..
http://www.sci.fi/~fta/MiG-29-2b.htm
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Enjoy your cabbage soup and Vodka for dinner comrades
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http://www.sci.fi/~fta/MiG-29-2b.htm
Like I said: "I can't see how any FOD would get stuck on those doors unless you somehow spray them with mud."
From your link:
"On top of all this, it was discovered that the unique FOD doors on the MiG-29's inlets were not stopping material from getting into the engine ducts. Since the doors retracted "up" into the inlet, debris that was kicked up by the nose wheel lodged on or at the bottom of the door seal and then was ingested into the engine when the door opened during the nose gear lifted off the ground during takeoff.
This problem was known from the earliest days. After the first four MiG-29 prototypes were evaluated, the nose gear was moved further back, but nose wheel "mud-flaps" or guards were still required to protect the engine from flying debris. It took until 1988 before all delivered aircraft were so equipped, therefore the initial batch of InAF aircraft had to be locally retro-fitted with mud guards and that activity was not completed until June 1992."
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It seems to me a similar solution could quite quickly be retrofitted to any engine. @
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motivated police call