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not making light of a serious thing ... 7
- Thread starter rb1957
- Start date
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1
- #21
Alistair_Heaton
Mechanical
All sort of strange stuff happens in inflight refuelling. Thankfully I have only heard the bar tales about it. And don't fancy having a shot to be honest.
I have heard it described as trying to shag a doughnut on a pendulum while on a rollercoaster.
I have heard it described as trying to shag a doughnut on a pendulum while on a rollercoaster.
A post from a twitter account, reportedly showing the F35 hitting the ground, and some closeups of the KC135
Brad Waybright
The more you know, the more you know you don't know.
Brad Waybright
The more you know, the more you know you don't know.
Alistair_Heaton
Mechanical
That's a whole heap more drag than a feathered engine.
That field isn't going to be usable for a long time with that much jet A pouring onto it.
JohnRBaker
Mechanical
Brad, yea, that's the same video I posted...
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
JohnRBaker
Mechanical
The pilot and co-pilot deserve a medal for that landing. I have to believe that the 'pucker factor' was really high as they approached that farm field.
The question now is, how in the heck are they going to get that plane out of that field?
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
The question now is, how in the heck are they going to get that plane out of that field?
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
Here's my 'free theory'.
Lotta smoke in the air from all the fires, especially in the Central Valley where this happened. Just an added bit of distraction and possibly turbulence.
Guy shows up to fuel.
Gets too focused on the basket-probe connection. As he's getting hooked in a hose reel malfunction starts it retracting. Focused only on it he chases it in.
About the time he notices how close he's gotten he's already fallen into Bernoulli's trap.
The air under the tanker's wing adds to the air over the fighter wing. The air over the fighter's wing adds to the air under the tanker wing.
More air - less pressure.
The pressure drop on the bottom of the tanker's wing drops it. Pressure drop on the top of the fighter's wing raises it.
This sucks the two craft together faster than anybody can react. The props are instantly shearing the nose off fighter turning it into a flying brick and it drops like one. While the tanker crew fights to re-level the tanker the fighter pilot is post haste bailing out of the brick.
Keith Cress
kcress -
Lotta smoke in the air from all the fires, especially in the Central Valley where this happened. Just an added bit of distraction and possibly turbulence.
Guy shows up to fuel.
Gets too focused on the basket-probe connection. As he's getting hooked in a hose reel malfunction starts it retracting. Focused only on it he chases it in.
About the time he notices how close he's gotten he's already fallen into Bernoulli's trap.
The air under the tanker's wing adds to the air over the fighter wing. The air over the fighter's wing adds to the air under the tanker wing.
More air - less pressure.
The pressure drop on the bottom of the tanker's wing drops it. Pressure drop on the top of the fighter's wing raises it.
This sucks the two craft together faster than anybody can react. The props are instantly shearing the nose off fighter turning it into a flying brick and it drops like one. While the tanker crew fights to re-level the tanker the fighter pilot is post haste bailing out of the brick.
Keith Cress
kcress -
JohnRBaker
Mechanical
Good theory, except that the video of the crash of the F-35B appears to show something that didn't have the flight path of a 'brick' but rather more like an aircraft that had simply lost power and was still 'flying' when it hit the ground.
Also, the atmospheric conditions looked pretty close to unlimited visibility in the video.
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
Also, the atmospheric conditions looked pretty close to unlimited visibility in the video.
John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
LittleInch
Petroleum
Doesn't have to be a malfunction.
It looks like if you connect then keep going faster than the tanker the hose retracts to prevent buckling and you can just follow it in.
Then sure the proximity effects come into play and bang.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
It looks like if you connect then keep going faster than the tanker the hose retracts to prevent buckling and you can just follow it in.
Then sure the proximity effects come into play and bang.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
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1
- #30
Alistair_Heaton
Mechanical
We don't know what they were doing.
Most US aircraft have a female receptor on the receiver and some one on the aircraft fly's the prod into it and the receiver just has to keep still. The F35B because of the big fan to do the VTOL as a extendable probe out the side of the nose and they use an unguided female basket. So a new to type pilot would have to relearn. Although if they were an old hand they would be used to flying harrier which I think is a basket job as well. The herc is relatively slow and produces a reasonable amount of dirty air behind it.
Although they are reasonably close together laterally they have a reasonable separation vertically to get them away from the dirty air from the props and wings.
The herc pilots did a great job with the forced landing, but I must admit my interest is mainly in why they couldn't fly to a runway with 2 engines still working.
It looks like they didn't have any flaps out which would indicate they had lost all hydraulics which would have effects on the amount of muscle force required to move the controls and a very much increased speed on touch down.
Main thing is there are no kids afterwards getting used to life without a mum or dad.
To get it out the field they will take the wings off and stick it on a low loader lorry and drive it out. It will be no bother to the US army Engineering corps, who will then remove all the contaminated soil from the fuel which will more than likely take more time and effort than getting the aircraft to a repair facility. The J is easier to strip down the the C and they have shipped them in C5's. The C had old age issues with wing spars running out of life and they replaced them, so the J they seem to have designed so that instead of having to take the whole lot to pieces to change the spar they can just detach the wings and replace them.
Most US aircraft have a female receptor on the receiver and some one on the aircraft fly's the prod into it and the receiver just has to keep still. The F35B because of the big fan to do the VTOL as a extendable probe out the side of the nose and they use an unguided female basket. So a new to type pilot would have to relearn. Although if they were an old hand they would be used to flying harrier which I think is a basket job as well. The herc is relatively slow and produces a reasonable amount of dirty air behind it.
Although they are reasonably close together laterally they have a reasonable separation vertically to get them away from the dirty air from the props and wings.
The herc pilots did a great job with the forced landing, but I must admit my interest is mainly in why they couldn't fly to a runway with 2 engines still working.
It looks like they didn't have any flaps out which would indicate they had lost all hydraulics which would have effects on the amount of muscle force required to move the controls and a very much increased speed on touch down.
Main thing is there are no kids afterwards getting used to life without a mum or dad.
To get it out the field they will take the wings off and stick it on a low loader lorry and drive it out. It will be no bother to the US army Engineering corps, who will then remove all the contaminated soil from the fuel which will more than likely take more time and effort than getting the aircraft to a repair facility. The J is easier to strip down the the C and they have shipped them in C5's. The C had old age issues with wing spars running out of life and they replaced them, so the J they seem to have designed so that instead of having to take the whole lot to pieces to change the spar they can just detach the wings and replace them.
From memory, the US approach to AAR is a bit more of a mixed economy than that. USAF heavy on boom and receptacle for certain, but USN and USMC have always been hose and drogue outfits.
Possibly the scariest video I ever saw was a series of attempts to prod a drogue hanging from a short hose off the back of the boom on a KE3A.
A.
Possibly the scariest video I ever saw was a series of attempts to prod a drogue hanging from a short hose off the back of the boom on a KE3A.
A.
davidbeach
Electrical
The hose and drogue system means that a single seat plane with wing tanks can be scrambled off a carrier to refuel somebody that's having difficulties landing and is beyond bingo distance of a land field. Just can't do that with boom system that requires somebody flying the boom in addition to somebody flying the plane. When I was working for the Navy I heard tales of pilots having a bad day in the middle of nowhere in the Indian Ocean that had to be refueled more than once before finally snagging the wire.
Alistair_Heaton
Mechanical
It's a bit weird to be honest with the polar opinions about the two different methods.
One costs significantly more than the other in both personnel and hardware.
And they both seem to carry the same level of sphincter clenching screw ups.
As for AAR involving mechanical Palm trees thats just an accident waiting to happen.
Thankfully I will never be involved in the procedure as either a giver or a taker.
One costs significantly more than the other in both personnel and hardware.
And they both seem to carry the same level of sphincter clenching screw ups.
As for AAR involving mechanical Palm trees thats just an accident waiting to happen.
Thankfully I will never be involved in the procedure as either a giver or a taker.
Perhaps less likely, perhaps not. Consider the chance that the Herc had an engine failure during the re-fuel operation, and the crew wasn't quick to feather the prop (or feathered the wrong one). The Herc slows down abruptly... banks toward the F-35 behind it... contact is made...
The escape route for a F-35 if there's trouble during re-fueling probably doesn't include slowing down any more. Given the relative slowness of the Herc and the design purpose of the F-35, there may not be much overlap in useful speeds that they both can use at the same time during the re-fuel operation. In that proximity to stall, there probably also isn't much margin for a turn, much less an abrupt one. Same reasoning for the ability to go up, therefore the main escape route for a re-fueling fighter jet is to go down. If the tanker has a problem that moves it into the jet's escape path, the options may be extremely limited, and very little time to choose another way to go.
Watch the opening credits of Dr. Strangelove to remind yourself of all the dancing about needed to do air-to-air refueling.
The escape route for a F-35 if there's trouble during re-fueling probably doesn't include slowing down any more. Given the relative slowness of the Herc and the design purpose of the F-35, there may not be much overlap in useful speeds that they both can use at the same time during the re-fuel operation. In that proximity to stall, there probably also isn't much margin for a turn, much less an abrupt one. Same reasoning for the ability to go up, therefore the main escape route for a re-fueling fighter jet is to go down. If the tanker has a problem that moves it into the jet's escape path, the options may be extremely limited, and very little time to choose another way to go.
Watch the opening credits of Dr. Strangelove to remind yourself of all the dancing about needed to do air-to-air refueling.
Alistair_Heaton
Mechanical
yep that is plausible.
I was also thinking about what would happen if a big slug of fuel came out and went down the intake of the F35B engine.
The UK does it from Hercs as well. But it uses a single centreline hose out through the back door which apparently gives cleaner air to sit in while pumping. And also gives the load master the opportunity to expose themselves while during pumping. Much to the delight of certain female warthog pilots.
The twin pods seems to give more dirty air.
I was also thinking about what would happen if a big slug of fuel came out and went down the intake of the F35B engine.
The UK does it from Hercs as well. But it uses a single centreline hose out through the back door which apparently gives cleaner air to sit in while pumping. And also gives the load master the opportunity to expose themselves while during pumping. Much to the delight of certain female warthog pilots.
The twin pods seems to give more dirty air.
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1
- #36
verymadmac
Mechanical
There is a test pilots story about the flight testing when the UK fitted the refuelling probes to the Avro Vulcan very rapidly in the lead upto the falklands war. Apparently they had a 3 knt margin on picking up up the basket. Too slow no fuel transfer, too fast and the impact wave would travel up the hose and back again breaking off the basket, at which point it would go down the inlet for No 2 engine which would surge and flameout spiting the basket out into the No 1 engine inlet, all the while hosing the windshield with fuel.
Lots of interesting ways for a refueling to go wrong.
Lots of interesting ways for a refueling to go wrong.
LittleInch
Petroleum
If I recall at the time it took 10 aircraft to get one bomber there with refuelling aircraft refuelling other refuelling aircraft in a planned hop and hop arrangement.
And on the last flight they broke the refuelling nozzle and had to land in Brazil. There's a plan of the refuelling system here
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
Eufalconimorph
Computer
A documentary on Operation Black Buck:
LittleInch
Petroleum
Sparweb, I don't think "laugh" is the right word here. A lot of people died and were injured in this conflict.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
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