I'd like to echo FODPlods' post - thank you to everyone who has contributed to a really good thread. To help in a couple of areas:

Effortless, the Pegasus wasn't really chosen over the Avon for the Harrier. It was specifically designed for the P1127, the Harrier's prototype ancestor, by Dr Stanley Hooker at Bristol Engines in close partnership with the Hawker team at Kingston, led by Ralph Hooper. Essentially, the Pegasus was an existing Bristol jet engine (I think it may have been the Orpheus) with a vastly oversized Low Pressure Compressor stage tacked on to the front via a plenum chamber which fed the two front 'cold' nozzles. As far as I know, the Avon was never a runner for the P1127. Much later, Rolls Royce did offer an 'interesting' propulsion option for the much larger (and later cancelled P1154 STOVL fighter/bomber which comprised two RR Spey engines plus a system of 'cross ducting' to feed for rotating nozzles. This was, to say the least, challenging, and the team stuck with the Bristol BS100.

To Tinny and others, the RAF (on a couple of occasions) did change Harrier engines at sea and they did have to retract the gear as per the shipboard procedure. In fact, the entire engine change gear for shipboard use was very different to that used on land, with much beefier trestles and side arms. The main reason for the 'lowered' position was the (quite justified) fear of having an aircraft high up on jacks swaying about on rolling decks. The 'Guide posts' were not much used, as there was a strong tendency for the guide collars attached to the wing to jam on to the posts - that created more problems than they solved.

PDR1 and others - yes, the design solution chosen for the P1127 fuselage and wing structure made perfect sense for a prototype. But (just my opinion), it didn't really past muster for a front line aircraft. As most readers here already know, the larger P1154, which was cancelled in 1967, had a large set of doors/panels on the underside of the fuselage to allow the much larger BS100 engine to be dropped down out of the aircraft without having to remove the wing. On the P1216 and other studies, some former colleagues of mine who worked on the P1216 expressed relief that it and other studies were never taken forward as a full design. The twin boom arrangement was a nightmare to design at an acceptable weight. More seriously, the BS100 engine (a much enlarged and redesigned Pegasus) had some serious issues, particularly with regard to the use of Plenum Chamber Burning (PCB) on the front nozzles. This generated a severe risk of hot gas reingestion (HGI) and thrust loss, as well as some probably insoluble issues with erosion of any landing surface.

Wingless, the Royal Navy's 'Invincible' class ships were aircraft carriers, albeit small ones. The 'through deck cruiser' designation was adopted to try to keep the procurement of the ships from being opposed by the RAF - the inter service climate in the MoD in the late 1960s/early 70s was simply poisonous, and this 'subterfuge' was a necessary expedient. The ships were not originally designed to take the Harrier, and it was a last minute change to get the lifts widened to accept the jet - before that, they were long thin 'slot' designs to take a folded Sea King. Small they may have been, but they served the nation well.

I absolutely agree that had the basic P1127/Kestrel design received a small fraction of the funding that went into P1154 and other programmes the UK could have developed its own more capable equivalent of the Harrier II in the 70 and 80s. In any case, the Sea Harrier and GR5/7/9 served the UK exceptionally well, providing 'bang per buck' that I think was unmatched. Having exceptionally good maintainers and operators was also essential to the aircrafts' successes. But (there's always a but, isn't there) the basic concept of a single large engine mounted in the centre of the aircraft with vectoring nozzles has, in my view, reached its limit. I agree with the basic conclusion reached by Lockheed that the best place for an engine on a supersonic aircraft is at the rear, with some of he power of the engine being used to generate (more efficient) cold thrust at the the front of the aircraft where it poses far less risk of HGI. I know others may disagree, and that's the great thing about forums like this - there is always room for other opinions. Long may that last.

Best regards as ever to all those who have, over the years, made STOVL work.

Engines

Essentially, the P.1127 was designed around the Pegasus. The available thrust was utterly marginal to demonstrate VTOL and transition, so the P.1127 was the smallest and lightest airframe that could be wrapped around the engine and maintainability be damned.

The Pegasus itself was designed to demonstrate the concept of a bypass engine with a large forward fan fitted with rotating nozzles, enabling VTOL. The first Pegasus sketches did not have vectoring on the core exhaust. I recall reading somewhere that Hawker observed to Bristol that the Sea Hawk had a bifurcated exhaust, so why waste that vertical thrust? The original idea was to match an Orpheus with Olympus compressor stages, but there can't have been much left of either original by the time the BE.53 ran.

Where it gets interesting is that Bristol was introduced to the concept of vectored thrust via France's Michel Wibault and his Gyroptere. This had four shaft-driven lift-cruise blowers, and the most powerful European turboprop at the time was the Bristol Orion. Stanley Hooker didn't like all the shafts and gearing and saw that a direct-drive axial fan with moving nozzles would be simpler and would also supercharge the core engine.

And, many years later, Paul Bevilaqua looked at the in-line tandem fan STOVL concept, which presented some nasty flow-switching issues, and decided to turn the front fan through 90 degrees with a clutch and gearbox, and separate the airflows, and so the F-35 was born.

And now you know the rest of the story...

There's a a very good book called 'Pegasus - The Heart of the Harrier' by Andrew Dow with the foreword written by John Farley (ISBN-13: 978-1848840423)
It gives an insight not only to the development of the engine (all variants) and the airframe, but also a history on VSTOL and the UK aviation industry at the time, especially between Bristol and Rolls Royce engine divisions.

This is an interview with Sqd Ldr Andy Edgel F-35 test pilot, ex 4 Sqdn and 800 NAS which gives an insight into landing both on deck and the work load involved.

The Pegasus started life as an early turbofan engine which used the Bristol Orpheus as the gas-generator. It came about because the original Orpheus had a novel design feature in that it saved the weight and cost of a centre bearing by making the mainshaft a large diameter tube whose stiffness was enough to avoid whirling without the additional support of a third bearing. Someone (Stanley Hooker, if I remember the story accurately) hit on the idea of adding what we would now call a second spool by running another shaft down the middle of this tube carrying a "big" fan at the front driven by a dedicated turbine on the back of this second shaft. This then led to thoughts of a 3-nozzle VTOL engine which had a straight-through (non vectoring) nozzle at the back, and the front fan air collected into two (vectoring) side nozzles. He drafted a brochure on this and discussed it with (again, IIRC) Ralph Hooper at Hawker. He had an idea for a light recon jet which landed vertically by pitching up to about 30 degrees so that the fixed and vectorable nozzles would cancel out to zero horizontal thrust.

At the time the Kingston project office were still hoping for a supersonic fighter project, but in the mean time they played with the VTOL concept to keep occupied. They had long since decided that any practicable VTOL jet had to be a "flat-riser" rather than any kind of "tail-sitter", so they went back to Bristol with the suggestion that the rear nozzle should be split and directed into two vectorable nozzles to produce the four-nozzle, fully-vectorable configuration we are now familiar with. They also made another suggestion which was to prove crucial. Bill Bedford had been in the US and had flown several of the US VTOL technology demostrators, including the Bell X-14 which he crashed. He crashed it because he got it into a situation where the powerful gyroscopic moments of the two engines running at high power but zero airspeed significantly exceeded the available control authority. Hawker's team had recognised that gyroscopics would be a significant issue on VTOL aircraft due to the negligible aerodynamic damping and stabilising forces in the hover. So Hawker suggested that the spools in this engine should counter-rotate, and that where possible effort should be made to try to make the gyroscopic moments of the two spools equal (but opposite).

As a result right from the very beginning the pegasus had negligible gyroscopic moments to upset hovering stability/controlability. This just left the discovery of "intake inertia moments" as the only nasty effect to be mitigated, but that's another story.

More than anyone wanted to know, I'm sure.

PDR

orca - so true; the effort needed by so many to keep fast jets operating is tremendous and way overlooked. I have thoroughly enjoyed reading the various contributions made here that give a glimpse of the importance and skill of those on the ground/ship that make the flying possible. Worthy of a book in itself; I find the detail on here fascinating and absorbing. The complexity of fast jets is amazing but it comes at a huge cost in maintenance.

Engines - thanks for the clarification and very illuminating posts on what issues there were around the Harrier and its concepts.

I have found all the comments here truly delicious! I could gorge on them no end. This thread is just like the Harrier project itself; it started with a simple humble question that grew into something more valuable than anyone could have imagined! All very interesting, informative and unique posts here giving a precious insight into an iconic historic aircraft. Many thanks to all posting here.

Great thread indeed.

My green shirts would have agreed with your division's views in heartbeat, Orca!

I think PDR's point about numbers (I would FA2s in there for completeness) is very poignant, and in a world of ever increasing costs it is easily missed, by politicians' starry eyes and others.

Cost comparison
 

I don't disagree, and the 10 for 1 statement was a bit of throwaway hyperbole harking back to Mountbatten's line that persuaded the Aussies to drop out of TSR2 in favour of a larger number of F111s. I remember back in 2009/10 when we were looking at extending the Harrier OSD beyond 2016 we decided 2018 was easy, 2023 was achievable but 2026 was going to be very difficult (much as my heart wished to say otherwise).

But my real point is one about the danger of having a small fleet of highly capable assets. The small numbers mean you're reluctant to risk losses, so you end up not prepared to risk using the extra capability. Another example would be my view that we'd have a more usable battle force with 8 CVSs than 2 QECs - because we could afford to risk losing a couple.

PDR

PDR, not really, risk that is.

In the case of the Falklands we were prepared to lose both carriers and lost several destroyers and escorts, hang the expense.

Less than 20 years earlier we were warned that the loss of one Vulcan would be the same level of political loss as the loss of an aircraft carrier.

It is a balance of political and not military acceptance of risk. To take two more recent examples: would we have risked the F35 in GW1? Would we risk an F35 in downtown Damascus?

​​​​​​I suspect Yes and No respectively.

I guess in an ideal world, it would be useful to have combat aircraft at both ends of the spectrum. Highly sophisticated and expensive aircraft like the F-35 and simple cheaper aircraft like the Harrier. The F-35 would be used in advanced airspace with advanced SAM and fighter threats; the Harrier could be used in more secure airspace such as Afghanistan, where advanced systems are largely absent.

There is logic in having both; but practicality leads to choosing one. If you have the money you can have both; the USA is doing exactly that by operating F-22/F-35 as well as U.S. Marine Harriers (up to about 2030 I believe). No other country has pockets quite as deep.

The Harrier is an iconic unique aircraft; but in its way so is the F-35. Not only is it the most advanced 5th Generation aircraft, it is likely to be the last solely manned fighter developed (in the USA/UK anyway). Tempest is to be manned/unmanned; that could change as systems develop even further.

Having put my handkerchief away and stopped sobbing over the passing of the humbly superb Harrier from the UK inventory, I went for a stroll through 'F-35 land' and found out for myself a bit more as to why this aircraft is essential for future combat airspace.

It comes in two words: stealth and systems. The value of stealth cannot be overrated and it doesn't have to make you invisible, just a lot smaller.

Modern SAM systems are so lethal they could detect and engage 4th generation fighters from a very long way away with high probability of a kill. Stealth negates these systems (and airborne systems); a stealthy aircraft would need to be engaged at closer ranges. With 4th generation fighters there was ECM and manoeuvring to defend against hostile weapon systems. Even if those '4th generation' weapons systems could engage you, they could be defeated with proper use of ECM and defensive manoeuvring (as clearly shown in Vietnam).

Now modern weapon systems are so lethal that once they get a lock on the target, the target is toast. Modern systems are much more robust in dealing with ECM and have high agility to deal with the manoeuvres of aircraft. To survive in this battle space an aircraft needs to be difficult to detect.

An Australian pilot gave an account of an engagement flying against F-22's; he said he could see the F-22 but couldn't put a weapon on it (the onboard weapon systems couldn't see the F-22). That amount of stealth is a game changer.

Now that you can penetrate the highly lethal battle space, the stealth aircraft can engage them directly or gather and distribute information on where the enemy assets are, allowing older fighters to stand off and lob weapons onto the targets found by the stealth aircraft, without having to hang around in that battle space. The stealth aircraft will clear a path through hostile airspace, a bit like a mine detector clearing a path through a minefield. You wouldn't want to run through a minefield but if someone had a detector to at least tell you where the mines are, you could get through it or blow up the mines found.

Came across the following interesting article describing what happens when one side has 5th generation and the other side doesn't.

The Reason No One Can Kill an F-22 or F-35: "It’s Nearly Impossible to Fight An Enemy You Can’t See."
September 2, 2018
https://nationalinterest.org/blog/bu...357?page=0%2C1

Example of stealth against 4th Gen. aircraft; T-38 Talons & F-15E's represented 4th Gen aircraft at BVR distances. Friendly forces were F-22 and Typhoon coordinating together. The idea was for the T-38's to try and close to visual range on the F-22 friendly forces. The T-38 pilots included an F-22 Test Pilot and prospective F-22 trainee pilot. So the attacking force had good knowledge of how the F-22 operates.

The flight of three T-38's didn't know what hit them; two went down without realising they were under attack by a Typhoon. The remaining T-38 began defensive manouvring against a threat still not seen and was shot down by a Typhoon coordinating with an F-22. The Typhoon coordinating with the F-22 was a combination described as "lethal".

An article here states that four F-22's with four F-15's achieved a kill ratio in exercises of 41-1.
"The Next Generation F-15 Is Packed With Missiles"
https://www.popularmechanics.com/mil...neration-f-15/

I read about the proposed F-15 upgrade to allow carrying of upto 24 missiles (F-15X).
https://theaviationgeekclub.com/boei...-air-missiles/

Its not hard to see what giving the F-15 the ability to carry upto 24 missiles is all about; replace the F-22 with F-35 and replace the Typhoon with F-15X; that combination will sweep 4thG fighters from the skies.

I read that this is one of the fundamental uses of the F-35; it will allow not just itself, but older 4thG aircraft to operate safely and effectively in the modern battle space. It is a force multiplier, in effect. Also cost effective if it allows older aircraft to be retained instead of being replaced by more expensive 5thG aircraft (USA plan was to replace the F-15 with 750 F-22's; only about 187 F-22's will be acquired).

Found useful interesting short clips on F-35 below.

F-35 Range information

Good information here on what makes the F-35 the necessary choice.
https://www.f35.com/about/capabilities

Benefits of 5th Generation Fighters

F-35 - A Pilot's Perspective

Taking a 4thG fighter all by itself into a modernised battle space is like taking a knife to a gunfight. An F-35 will change that.

This looks to me like very specific target/weapon matching. Whilst the PK is over 0.5 how do you deal with three, or a dozen etc?

Some good points in recent posts. :) Of course, the arguments about capabilities and relative enemy performance need to be kept in context so that the argument is not one of a "perfect" capability that in reality is less than that. Also, if you put your tiny force of super-capable machines on board a highly vulnerable transporter / launch system, you might have the almost proverbial case of "all your eggs in a weak basket". :oh:

OAP

Top brass seem not to be that interested in their low end aircraft; I understand the USAF wasn't particularly thrilled at having an A-10 until the US Army said it would make one itself. When it came along, it was treated with disdain in the USAF, despite its success in combat.

The CAS mission no longer has a dedicated aircraft in the UK. The Harrier did superbly in CAS in Afghanistan from what I heard. F-35 or Typhoon seems overkill in such a scenario. From what I read, including parliamentary debates, there was no real need to replace Harrier in that theatre. There were suggestions that the Harrier was being 'killed off', similar to rumours now about the A-10 in the USAF.

Was the Harrier unfairly assassinated? Would we use an F-35 to do the type of job Harrier did in Afghanistan? No, I suspect.

Would a pairing of F-35 with Harrier have been worth it? Both those aircraft could operate off the carriers and give greater flexibility in CAS role.

Orca, my point really is how the OTR is determined. If we consider a mass attack of whatever then you need to counter with mass. You may not have the luxury of plinking one at a time. Refining your weapons systems to the extent that you have a PK approaching 0.99 and collateral 0.01 may limit your abilities to up your game in a target rich environment. The F15x missile truck would address that issue, as would a 3-ship of Buffs.

Pontious, are we not discussing a scenario here that has 5th Gen stealth as a pre-requisite for survivability? Therefore, missile trucks and Buffs would not survive.

OAP

OAP, I agree with that too. My caution is that procurement should not go so far as it ensure killing a Hilux and losing the capability of killing an armoured battle group.

Whilst the F35 mine clearance analogy may work a counter is more mines!

Yes, true. However, in my opinion, we cannot know all the details of the perceived threats and the real weapon effectiveness of the latest weapons against them. It seems that very little information is given to us about the politically led requirements that our forces are demanded to achieve. That leaves us to contemplate the general concepts of weapon systems and policy. :hmm: Cheers

OAP

Lowering the aircraft nose to lift the wing and remove the engine was nothing to do with stability, it was to do with getting the aircraft in the rigging position, and thus the wing and engine coming out of the aircraft straight. In the RAF we would "EITHER" retract the nose leg and drop the aircraft nose low, or remove just the nose wheel, but still drop the aircraft nose low. It was possible to use the same hoist to remove the ECU & Wing, but this meant moving the hoist point around, so we "RARELY" used the same hoist for both operations. With a well versed crew, we could get an engine change with all the associated work done in two 8 hour shifts, the biggest hassle was the tie down runs with associated hot air leak checks - then it was over to the two wing master race to air test the machine, complete with perf hovers if we could - if we were in the field or somewhere else, we could enter a lim for "no limiting hovers" which basically meant you could hover the machine if there was an escape route available (Runway) but to a field pad or similar, then no!

Just had a peek at the modern threats to aircraft. There is one threat that is the 'Daddy' of them all and it is really bad news. The Russian S-400 Triumf (NATO code SA-21 Growler). It can reach out to 400km, up to about 30km high (185km on Wiki for specific missile), down to about 5m and travelling at 5,000 m/s (MACH 15). It is highly resistant to jamming. It is extremely mobile, can be setup quickly and with only three personnel. It fires four different missiles for various range engagements and can engage 80 targets simultaneously. It can engage all manner of airborne threats, including ballistic and cruise missiles. If that wasn't bad enough, they are selling it all over the place. It will be in more countries than MacDonalds by Christmas.

I don't know about F-35, I would be wanting the Starship Enterprise and Klingon cloaking device before messing with that.

The nearest system we have apparently is the Patriot missile system that has a range of about 100km up to about 25km altitude. That's a whole lot less than the S-400. There is an upgrade in progress (Patriot Advanced Capability - 3) but I don't imagine it will get anywhere near the S-400.

How did that happen? How did Russia get such a jump ahead of the West in SAM capability? Apparently only the F-22 is capable of confidently attacking the S-400, with its better stealth properties. The F-35, with reduced stealth, is said to be at risk to this system, especially as the stealth of the F-35 diminishes significantly when not targeted from the frontal aspect.

Government statements have indicated the Typhoon will be in-service to 2040. 4thGen aircraft wont get near an S-400. If I was a Typhoon pilot I would ask for a F-35 or a pay rise at least. Going against a S-400 in anything other than an F-22 is said to be risky; anything less than a F-35 would be re-enacting the charge of the Light brigade.

The S-400 is a monumental advance in SAM capability; but what leaves me gobsmacked is that we have nothing near it. Any tin-pot dictator could buy one and instantly get a high level of air defence capable of handling nearly anything that could be thrown at it.

It would interesting to know whether unmanned fighters, with their much higher 'G' capability, would be able to out-manoeuvre these SAM missiles, in a similar way to how that was done in Vietnam. I doubt it and in any case ripple firing these SAM's would get the aircraft in the end.

Together with the potential of new stealth defeating systems (such as quantum radar, etc.) and laser weapons downing aircraft, it seems one possible scenario of the not too distant future is a battle space where aircraft have become as vulnerable and outdated as cavalry.

Quick overview of S-400
"Russia's S-400 Is Way More Dangerous Than You Think"
January 18, 2018
https://nationalinterest.org/blog/th...ou-think-24116

Good detailed overview of S-400
"Technical Report APA-TR-2006-1201"
Almaz S-300P/PT/PS/PMU/PMU1/PMU2 / Almaz-Antey S-400 Triumf / SA-10/20/21 Grumble / Gargoyle

Wiki
https://en.wikipedia.org/wiki/S-400_missile_system

Why India Is Buying Russian S 400 Instead Of America’s Patriot Pac 3?

tqmatch,
You've obviously done a lot of ship borne engine changes then...............

Brian, an ECU is a complete engine assembly with all the extra components fitted to the basic engine. Think a car engine and then the water pump, alternator, head box etc. A 'Simple' engine change involves removing the engine, stripping all the ancilliaries off it, refitting them to the new engine and reinstalling it. Changing an ECU, all out all in. The paperwork is probably simpler too as all the components will have been serviced and service intervals reset.

We once needed an engine change overseas. The engine was removed and packaged by an aptly named Sgt Hammer. The replacement was delivered, ours was loaded on the transport and back to UK. When we unpacked the engine we found just an engine and not a complete ECU. So we had another week in the Sun.

WW,
The details in open source always sound scary. However, as I pointed out in my post, you cannot know the real performance and capabilities from reading that sales blurb. The actual effectiveness and vulnerabilities of weapon systems are kept very closely guarded for obvious reasons. However, where the general characteristics of some things are known, we can debate their merits. Cheers

OAP

Brian,
To expand a bit on PN's answer, ECU stands for Engine Change Unit and is a manufacturer's / maintenance term.
That is probably why you never saw it written on the aircrew side.
Nowadays, it is usually called QEC (U) Quick Engine Change (Unit) and is used by Airbus and Boeing in their maintenance manuals plus GE and RR have specific definitions as to what constitutes a QEC.
There is also EBU - Engine Build UP which is a Boeing term.

I don't know anything about the S400 apart from what I read here or wiki, but there is a clue in the quote. The ignorant assume that 400km and 5m are one corner of the flight envelope. The 4 different missiles suggest each missile is optimised for a specific part of the MEZ. So what is new compared with earlier, Nike/Hawk/Rapier layered defence? What is new compared with a 400km range missile retired by the US almost 50 years ago?

What is apparently new is the ability for a launch team to operate 4 different missiles. The ability to engage 80 targets simultaneously is awesome, but you also need 80 plus missiles plus reloads. Now the logistics must be awesome. Unless they are supplied wholesale as in Vietnam they could soon be shot out.

Impressive as the system undoubtedly is it will have wealnesses; I think logistics is one. Analysts will find a weakness somewhere that can be exploited.

orca - I have been out of the combat aircraft 'sphere' for a very long time now. Some of the articles I read were years old, so I probably am the very last person to hear about the S400! I came across another article about phones that can fit in your pocket; I am going to get one when they come out! Such is my Robinson Crusoe existence, without the palm tree's unfortunately.

I came across the S400 a while ago but didn't check out its specs. My comments were a little tongue-in-cheek but I was impressed by how far the goal posts had moved.

I guess principles of SAM systems are fundamentally the same and so the initial means of dealing with them can still be used, along with more modern methods. SAM = radar + fire control + missile + data-link; I suppose this equation is still valid although there is probably a bit more too it now.

One thing that wont change are the laws of physics. A missile is still a pole with short stubby fins on it. A missile that can go 400km is going to be big and heavy. It has a long reach but its not invincible. When a SAM turns its 'headlights' on, its there for all to see.

Radar is still limited by the curvature of the earth, so seeing a jet on the deck beyond a flat 25 miles or so is still problematic unless you have airborne radar.

I read an account of a Gulf War A-10 pilot who was shot at by a SAM at night. He saw the launch and tracked the 'flame' of the SAM and began to 'dance'. Then the flame went out and he had to time his moves based solely on his predictions of what the now invisible SAM was doing. That's one hell of a way to earn a living but it shows the defensive tools and training work.

I suspect that today's high threat environment puts emphasis on team work more than ever. The S400 is a clear marker of how much more lethal the battle space is becoming. No doubt technology will continue its game of 'leapfrog', where one advance is negated by another.

What was interesting in reading some government published documents was that it was pointed out that the 6thGen Tempest does not necessarily refer to a single aircraft; Tempest could actually be the name for a system of several components that deliver the required capability.

OAP - you are right. Rules of Life: No.1 Never eat yellow snow; No.2 Never trust a glossy brochure. I take your points exactly. The theoretical capabilities can be far different to the 'every day' real world capabilities. I 'over egged' it a bit in making the point that the systems of today are highly lethal and getting more so.

Manufacturers can be over enthusiastic with their 'new born babes'. Back in the beginning of the SAM/missile age many thought the missile had killed the dogfight; they thought once the missile was launched it was game over for the poor target. The manufacturers were eager to sell their wonder weapons and they undoubtedly sold them to themselves first and made gross claims that these miniature kamikaze's could not be dodged if launched within their limits. When these wonder weapons went to war in Vietnam, they did not work as advertised.

Like wise the Sea Harrier in the Falklands. I do believe an initial serious assessment by some outside the FAA was that they would all be lost in one or two weeks and were no match for the supersonic jets and missiles. The pilots had other idea's but it took putting the systems and the personnel to war to reveal reality. As you say, no matter what the brochure says it will take putting those systems to the test to know how effective they really are.

The proliferation of highly capable weapon systems like the S400 may give some crazy person the impression they are now more protected than they really are, leading to them starting something somewhere. As well as the battle space impact of these systems they may also have a political space impact. They may destabilise various regions.

Thanks to you both for your sharing the benefits of your experience; this thread has been a great read.