Amazingly cool and interesting plane footage

Amazingly cool and interesting plane footage

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Discussion

Condi

18,741 posts

186 months

Tuesday 9th February 2021
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Eric Mc said:
What would be your solution?
Probe could have an elbow in it, so extends down and then forwards?

Given the other engineering challenges involved with the system, you would have thought that this wouldn't have been the biggest!

RizzoTheRat

26,786 posts

207 months

Tuesday 9th February 2021
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But if you mount the tip too low it's presumably a lot harder for the pilot to line on the drogue (which is already pretty difficult judging by that video). No idea how far down the pilot can see, but you'd need to be able to see a way below the tip in order to judge your sink rate relative to the drogue.

MartG

21,786 posts

219 months

Tuesday 9th February 2021
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Presumably it could only happen with the probe extended

RizzoTheRat

26,786 posts

207 months

Tuesday 9th February 2021
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Scary looking cable break on USS Eisenhower, apparently injured 8 sailors, did $200k of damage, and the E2 got down to 20 feet above the sea

https://www.youtube.com/watch?v=r-EHwYOfY94

Dr Jekyll

23,820 posts

276 months

Tuesday 9th February 2021
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Was the E2 meant to land that fast?

FourWheelDrift

90,908 posts

299 months

Tuesday 9th February 2021
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Suggested video on the link is an interview with the pilot - https://www.youtube.com/watch?v=da39t2DNYqU

RizzoTheRat

26,786 posts

207 months

Tuesday 9th February 2021
quotequote all
"We saw a lot of water in front of the aircraft, then we started to see water and some sky, and then all sky so..." laugh

take-good-care-of-the-forest-dewey

6,477 posts

70 months

Tuesday 9th February 2021
quotequote all
Eric Mc said:
What would be your solution?
To fundamentally question why that failure mode is possible and start from there. Engineers are not infallible and aerospace design is often hampered by legacy practices and concepts. Ex RR here.

The selected solution may be the least risky, but having worked in engineering for 20 odd years (some of that defence), it is also possible that the solution used in the vid is not the safest but the cheapest safest that works with the existing infrastructure. Military risk tolerance is much higher.

As I've so far skirted the question, i would be looking why probe to drogue fuelling isn't possible. E.g tanker approaches helo.

It's clearly possible for a helo to carry probe and drogue.

https://i.stack.imgur.com/Uk9n9.jpg

RizzoTheRat

26,786 posts

207 months

Tuesday 9th February 2021
quotequote all
take-good-care-of-the-forest-dewey said:
To fundamentally question why that failure mode is possible and start from there. Engineers are not infallible and aerospace design is often hampered by legacy practices and concepts. Ex RR here.

The selected solution may be the least risky, but having worked in engineering for 20 odd years (some of that defence), it is also possible that the solution used in the vid is not the safest but the cheapest safest that works with the existing infrastructure. Military risk tolerance is much higher.

As I've so far skirted the question, i would be looking why probe to drogue fuelling isn't possible. E.g tanker approaches helo.

It's clearly possible for a helo to carry probe and drogue.

https://i.stack.imgur.com/Uk9n9.jpg
You mean a helicopter to run out a fuel line and drogue and the tanker to plug a probe in to it? The drogue, cable reel and associated plumbing would be way heavier than the current approach of fitting a probe to the helicopter, taking up valuable cargo or fuel payload. I'm assuming nobody's ever fitted a drogue to a helicopter to use as a tanker due to range and payload limitations though.

take-good-care-of-the-forest-dewey

6,477 posts

70 months

Tuesday 9th February 2021
quotequote all
RizzoTheRat said:
You mean a helicopter to run out a fuel line and drogue and the tanker to plug a probe in to it? The drogue, cable reel and associated plumbing would be way heavier than the current approach of fitting a probe to the helicopter, taking up valuable cargo or fuel payload. I'm assuming nobody's ever fitted a drogue to a helicopter to use as a tanker due to range and payload limitations though.
Did you look at the picture I linked?

RizzoTheRat

26,786 posts

207 months

Tuesday 9th February 2021
quotequote all
Yes, it shows a Blackhawk refuelling from a C-130 which is trailing two drogues.

ETA: Interesting that the C-130 has the back door open, anyone know if that's standard practice for the crew to keep a better eye on the proceedings?

Edited by RizzoTheRat on Tuesday 9th February 18:04

take-good-care-of-the-forest-dewey

6,477 posts

70 months

Tuesday 9th February 2021
quotequote all
RizzoTheRat said:
You mean a helicopter to run out a fuel line and drogue and the tanker to plug a probe in to it? The drogue, cable reel and associated plumbing would be way heavier than the current approach of fitting a probe to the helicopter, taking up valuable cargo or fuel payload. I'm assuming nobody's ever fitted a drogue to a helicopter to use as a tanker due to range and payload limitations though.
It's a balance of risk though isn't it. You could argue that not armouring helos reduces weight and increases payload / range. It wasn't long that air cav pilots were willing to trade off payload / stamina / agility for additional protection in Vietnam though.

If helo refueling is risky in daylight and OK weather conditions, at night, with fatigue as a factor, it only increases the risk significantly.

I freely admit I'm not an IFR design engineer and that may be the best solution... But I suspect it's the lowest risk that is cheapest, and fits with the existing infrastrure. Rather than safest.

ETA... Seems it is practical for refuelling in hover.

http://www.alfons-haar.com.au/news/new-helicopter-...




Edited by take-good-care-of-the-forest-dewey on Tuesday 9th February 18:37

MartG

21,786 posts

219 months

Tuesday 9th February 2021
quotequote all
take-good-care-of-the-forest-dewey said:
ETA... Seems it is practical for refuelling in hover.

http://www.alfons-haar.com.au/news/new-helicopter-...
The hose is winched up from the ship using the helicopter's rescue winch - no heavy equipment is added to the aircraft

MartG

21,786 posts

219 months

Tuesday 9th February 2021
quotequote all
Why was the Bf109 slower than a P-51, which had an engine 30% smaller than the Messerschmidt ?

https://www.youtube.com/watch?v=sTD7DqXfRno&fe...

eccles

13,973 posts

237 months

Tuesday 9th February 2021
quotequote all
take-good-care-of-the-forest-dewey said:
Eric Mc said:
What would be your solution?
To fundamentally question why that failure mode is possible and start from there. Engineers are not infallible and aerospace design is often hampered by legacy practices and concepts. Ex RR here.

The selected solution may be the least risky, but having worked in engineering for 20 odd years (some of that defence), it is also possible that the solution used in the vid is not the safest but the cheapest safest that works with the existing infrastructure. Military risk tolerance is much higher.

As I've so far skirted the question, i would be looking why probe to drogue fuelling isn't possible. E.g tanker approaches helo.

It's clearly possible for a helo to carry probe and drogue.

https://i.stack.imgur.com/Uk9n9.jpg
I'm confused, your solution to the problem is for probe and drogue, which is what's going on in the video in question.

Then you show a picture of a Helo doing exactly the same as what's going on in the video as a solution. confused

take-good-care-of-the-forest-dewey

6,477 posts

70 months

Wednesday 10th February 2021
quotequote all
eccles said:
I'm confused, your solution to the problem is for probe and drogue, which is what's going on in the video in question.

Then you show a picture of a Helo doing exactly the same as what's going on in the video as a solution. confused
Ignore the pic. Posting on phone and it appeared that the helo was trailing a drogue.

My suggestion was to look at viability of probe to drogue fuelling. I. E helo leads tanker.

This was dismissed by others as too much weight in helo for drogue kit.

I was humouring Eric with an answer as to what would I look at design wise. In reality, no designs originate from a single person. It's a multi-discipline team.

But I do suspect my point stands... The current solution isn't the safest... It's best fitvwith current infrastructure with currently torreable risk.

They have ooex that the risk is there. Viewed through Haddon cave prism, it would be tricky defence if they lost a helo or two in a similar accident.

Eric Mc

123,842 posts

280 months

Wednesday 10th February 2021
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And the alternative is.......?


take-good-care-of-the-forest-dewey

6,477 posts

70 months

Wednesday 10th February 2021
quotequote all
Eric Mc said:
And the alternative is.......?
To put together a multi-disciplinary team and review why that sort of accident is considered to be tolerable...

I'm perfectly entitled to have an opinion on a very obvious flight risk captured in the video. You may take a cavalier attitude in your role when it comes to risk, but as I've worked in the defence sector on highly dangerous kit over the years, I tend to tend to have a more questioning attitude when near misses occur.

Go and read Haddon-Cave's report to see why this important.

eccles

13,973 posts

237 months

Wednesday 10th February 2021
quotequote all
take-good-care-of-the-forest-dewey said:
Eric Mc said:
And the alternative is.......?
To put together a multi-disciplinary team and review why that sort of accident is considered to be tolerable...

I'm perfectly entitled to have an opinion on a very obvious flight risk captured in the video. You may take a cavalier attitude in your role when it comes to risk, but as I've worked in the defence sector on highly dangerous kit over the years, I tend to tend to have a more questioning attitude when near misses occur.

Go and read Haddon-Cave's report to see why this important.
It's hardly a common incident requiring a full redesign. Using your solution the exact same thing could happen with the drogue hitting the tail rotor.

Eric Mc

123,842 posts

280 months

Wednesday 10th February 2021
quotequote all
take-good-care-of-the-forest-dewey said:
To put together a multi-disciplinary team and review why that sort of accident is considered to be tolerable...

I'm perfectly entitled to have an opinion on a very obvious flight risk captured in the video. You may take a cavalier attitude in your role when it comes to risk, but as I've worked in the defence sector on highly dangerous kit over the years, I tend to tend to have a more questioning attitude when near misses occur.

Go and read Haddon-Cave's report to see why this important.
Aha - the committee approach. That works.

I was thinking more of the technical solution. There are limited ways to get fuel from one aircraft to another in mid-air. I was just wondering what ingenious method you might come up with that hasn't been tried before now.