Tempest Manned Unmanned Fighter Concept

Absolutely. REPLICA bounced us into F-35.

Much of stealth is about manufacturing tolerances as much as shape. Some comparisons with panel fit on Russian aircraft might be made here; I don't know about Chinese.

I was shown at first hand over 25 years ago what BAE was doing with DB/SPF. It was very impressive.
Manufacturing and okerances May it may not be a big issue about ‘stealth.’

most of its down to what can be used to detect you in the first place

realising that mounting a an engine on a sprung soundproof box isn’t too much about manufacturing tolerances. It’s about understanding that sound transmits through water.

the WW2 German understanding that bolting rubber tiles onto one of their U boats wasn’t about tolerances. It was an understanding that ASDIC was absorbed by the rubber and not emitted.

Realising that flat surfaces bounce back radar signals more than angled surfaces isn’t about manufacturing tolerances. It’s about understanding how radars work.

nothing is invisible to radar. The limiting factor has always been the radar return interpretation. As processing power continues to increase, the easier it becomes to interpret those returns.

Stealth for me is how AI is being portrayed as a panecea. So far, all I’ve seen with AI is a load of sensors with better standards of programming in order to process. Every example of AI I’ve seen has never been more than a better standard of programming for algorithms. Even relatively straightforward stuff I can do in excel still amazes people.

We use the terminology stealth when in reality we actually mean camouflage.

it would be a brave man who flies a stealth aircraft into heavily defended airspace without having first identified the existing threats, mapped out the weaknesses in the air defence and sent up some for of jamming aircraft to assist or some form of distraction.

when people think they’ve overcome the radar issue, they’ll just try and use something else that can detect things non radar related.


Air warfare has transitioned away from the army equivalent of brightly dressed soldiers forming up in square and is onto the natural progression of decoy and camouflage to increase survivability.
 

Cold_Collation

LE
Book Reviewer
Manufacturing and okerances May it may not be a big issue about ‘stealth.’

most of its down to what can be used to detect you in the first place

realising that mounting a an engine on a sprung soundproof box isn’t too much about manufacturing tolerances. It’s about understanding that sound transmits through water.

the WW2 German understanding that bolting rubber tiles onto one of their U boats wasn’t about tolerances. It was an understanding that ASDIC was absorbed by the rubber and not emitted.

Realising that flat surfaces bounce back radar signals more than angled surfaces isn’t about manufacturing tolerances. It’s about understanding how radars work.

nothing is invisible to radar. The limiting factor has always been the radar return interpretation. As processing power continues to increase, the easier it becomes to interpret those returns.

Stealth for me is how AI is being portrayed as a panecea. So far, all I’ve seen with AI is a load of sensors with better standards of programming in order to process. Every example of AI I’ve seen has never been more than a better standard of programming for algorithms. Even relatively straightforward stuff I can do in excel still amazes people.

We use the terminology stealth when in reality we actually mean camouflage.

it would be a brave man who flies a stealth aircraft into heavily defended airspace without having first identified the existing threats, mapped out the weaknesses in the air defence and sent up some for of jamming aircraft to assist or some form of distraction.

when people think they’ve overcome the radar issue, they’ll just try and use something else that can detect things non radar related.


Air warfare has transitioned away from the army equivalent of brightly dressed soldiers forming up in square and is onto the natural progression of decoy and camouflage to increase survivability.
That wasn't quite my point.

Shape/signature can be compromised if tolerances and fit aren't as good as they can be. Hence why a lot of earlier-generation stealth aircraft had filler put in along panel seams.

Hence why those aircraft in-theatre look a lot more pristine than those that are not - modellers might like to portray such as the F-35 with all those zigzag panel lines showing because it's interesting, and indeed there are plenty of images of the real thing flying in that condition, but not in-theatre.

REPLICA was shaped to minimise signature - but it was also built to demonstrate that we have the ability to manufacture to very close tolerances.
 
That wasn't quite my point.

Shape/signature can be compromised if tolerances and fit aren't as good as they can be. Hence why a lot of earlier-generation stealth aircraft had filler put in along panel seams.

Hence why those aircraft in-theatre look a lot more pristine than those that are not - modellers might like to portray such as the F-35 with all those zigzag panel lines showing because it's interesting, and indeed there are plenty of images of the real thing flying in that condition, but not in-theatre.

REPLICA was shaped to minimise signature - but it was also built to demonstrate that we have the ability to manufacture to very close tolerances.
Very close tolerances increases cost. (Although I’d never advocate a return to Nimrod manufacturing methods where each airframe is unique.)

there was an old story about Packard making Merkin Engines. They couldn’t make them like Rolls Royce could as the workforce weren’t artisans.

they invented the gasket to simplify production.

hiw true it is I don’t know.

you can have the most precision piece of equipment in the world, but as we all know, the AK is extreme reliable because of its loose tolerances.

mid tolerances are that much of a problem, they’d deal any gaps with filler.

I don’t know how much of the angular shapes are down to right tolerancing. Personally I’d have put more weight behind analysing what shapes deflect radar and the advent of fly by wire and the associated software in order to make the aircraft so inherently unstable that the onboard flight systems can handle the unstable shape.

I’ll do some reading up on replica though. Thanks for pointing it out.

I’ve got a feeling though that most of the ‘stealth’ features are just what comes along with generation 6 aircraft. A bit like stabilised gun platforms and composite/reactive armour. As counter measures to what you have come along, you need to take the next technological step to keep ahead.
 

Cold_Collation

LE
Book Reviewer
Very close tolerances increases cost. (Although I’d never advocate a return to Nimrod manufacturing methods where each airframe is unique.)

there was an old story about Packard making Merkin Engines. They couldn’t make them like Rolls Royce could as the workforce weren’t artisans.

they invented the gasket to simplify production.

hiw true it is I don’t know.

you can have the most precision piece of equipment in the world, but as we all know, the AK is extreme reliable because of its loose tolerances.

mid tolerances are that much of a problem, they’d deal any gaps with filler.

I don’t know how much of the angular shapes are down to right tolerancing. Personally I’d have put more weight behind analysing what shapes deflect radar and the advent of fly by wire and the associated software in order to make the aircraft so inherently unstable that the onboard flight systems can handle the unstable shape.

I’ll do some reading up on replica though. Thanks for pointing it out.

I’ve got a feeling though that most of the ‘stealth’ features are just what comes along with generation 6 aircraft. A bit like stabilised gun platforms and composite/reactive armour. As counter measures to what you have come along, you need to take the next technological step to keep ahead.
It's a true story. It was me that related it on here.

The Packard guy asked how close they machined... then said they'd go closer. The Packards are still the more sought-after Merlins because they're tighter.

Very close tolerances increase cost, to use your Merlin example, if a lot of hand-fettling is needed.

What REPLICA helped to demonstrate is that BAE's digital manufacturing processes are world-class.

An AK comparison is meaningless. Old steam engines were built very loose and packed with grease to cope with expansion and contraction. Build them tighter, and they'd just jam. It meant that they were less efficient, though.

REPLICA demonstrated shape (don't be surprised to see how much like Tempest it looks) but it also demonstrated close tolerances.
 
Actually not surprised by this, always felt the 2bn was insufficient to get the programme moving

It’s uk defence journal if he isn’t arguing with Russian trolls he is pointing out that planes fly of aircraft carriers, ships are built in Scotland, and he is a key worker.
 

rampant

LE
Kit Reviewer
Book Reviewer
It's a true story. It was me that related it on here.

The Packard guy asked how close they machined... then said they'd go closer. The Packards are still the more sought-after Merlins because they're tighter.


Very close tolerances increase cost, to use your Merlin example, if a lot of hand-fettling is needed.

What REPLICA helped to demonstrate is that BAE's digital manufacturing processes are world-class.

An AK comparison is meaningless. Old steam engines were built very loose and packed with grease to cope with expansion and contraction. Build them tighter, and they'd just jam. It meant that they were less efficient, though.

REPLICA demonstrated shape (don't be surprised to see how much like Tempest it looks) but it also demonstrated close tolerances.

Fraid not, that myth has recently been scotched by Calum Douglas in this tome

Amazon product
Rolls Royce Tolerances were tighter than those used today by F1 Engine Manufacturers

Calum covers this in this thread here

An interesting read about the Packard built Merlin engine.

He's Snowygrouch

Twitter links



 
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Cold_Collation

LE
Book Reviewer

rampant

LE
Kit Reviewer
Book Reviewer
Ouch.

I was at a publishing house that ran a story from Leonard Setright which set it out as fact.

Calum has done has huge amount of work in the archives to produce his book, and this original archival digging has slain a few mythological beasts. Well worth buying.

These two threads by Naval Aviation Historian Matthew Willis shows how important archival work is and how errors creep in and how myths can be punctured


 

Cold_Collation

LE
Book Reviewer
Calum has done has huge amount of work in the archives to produce his book, and this original archival digging has slain a few mythological beasts. Well worth buying.

These two threads by Naval Aviation Historian Matthew Willis shows how important archival work is and how errors creep in and how myths can be punctured


Interesting. The account published was quite specific as to what happened/was said.

I suspect that a former employer could be quite angry. On the other hand, Setright has been dead 16 years.
 
The difference between a Rolls Royce Merlin and a Packard Merlin was basically Packards used paper gaskets.

RR exquisitely hand fitted and scrapped their joints - and they leaked.
Packard being car engines makers, had their engineers look at the engine and said, Sod that hand fitting, fly cut the faces with a bigger gap and put in paper gaskets. RR engineers were horrifird by such cheap and nastyness, but it worked, perfectly, and the Packard engines were much faster to produce, and they didn’t leak.

It was a standing joke you could always spot the planes with RR Merlins, they always had a drip tray under the engines.
.
 

rampant

LE
Kit Reviewer
Book Reviewer
The difference between a Rolls Royce Merlin and a Packard Merlin was basically Packards used paper gaskets.

RR exquisitely hand fitted and scrapped their joints - and they leaked.
Packard being car engines makers said, Sod that, fly cut the faces with a bigger gap and put in paper gaskets. RR engineers were horrifird by such cheap and nastyness, but it worked, perfectly, and the Packard engines were much faster to produce, and they didn’t leak.

It was a standing joke you could always spot the planes with RR Merlins, they always had a drip tray under the engines.
.

See above, by the Historian and former F1 Engine Designer Calum Douglas, hand fettling to tiny tolerances was not feasible
 

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