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20 years since them slags smashed into the twin towers...

Started by Butchers Blind, September 10, 2021, 12:32:14 AM

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buzby

Quote from: MikeP on September 21, 2021, 03:16:33 AM
Until they broke up...

https://www.youtube.com/watch?v=IYRKFkkyxh0
That was VX770, the first prototype that had already led a hard life before being handed over to Rolls Royce to use as an engine testbed. It was very different to a production standard Vulcan - the Olympus engines were not ready so it was built to use the smaller Rolls Royce Avon engines instead, and was later fitted with Armstrong Siddeley Sapphire engines used in the Victor Mk1. To make up for the lack of power, it was built a lot lighter than the production versions, and was also initially built without wing fuel tanks, which were later retrofitted. The early B1 prototypes, and VX770 in particular, had very different wing structures to the production versions. Issues had been seen by Avro with stress-related cracking in the leading edge spar and wing ribs on both VX770 and it's sister VX777 (the first to be powered by the intended Olympus engines) and they had implemented a system of pre-flight checks to look for them. The B1 production versions were built with a redesigned, much stronger lower front spar to counteract this, and the later B2 version had a totally different 'kinked' leading edge design to reduce aerodynamic stresses in that area.

VX770 was handed over to Rolls Royce in 1957 to use as a flying testbed for the development of the Conway engine for the Boeing 707, Douglas DC-8, Vickers VC10 and in military form the Victor Mk2 (one of the reasons it was selected for this task was due to it having the same Sapphire engines fitted as the Victor Mk1). The Conway was the first high-bypass turbofan (where most of the thrust is produced by cold air being blown around the outside of the engine core by a large turbine attached to the front), and as such when fitted to the Vulcan testbed the vibrations and stresses in the wing from the massive increase in airflow though the intake ducts over it's original engines would have been very different to what it had been designed for.

In the subsequent Board Of Inquiry,. Rolls Royce's engineer on the panel stated that the accident had been caused by the crew exceeding the agreed limits of the aircraft. The panel were not told that Avro considered that statement to be invalid - Avro and RAF pilots had been demonstrating the Vulcan with similar displays for the past 6 years. VX770 however had led a particularly punishing previous life being pushed to (and sometimes beyond) it's limits by test pilots in aerobatic displays to 'show off' the Vulcan at airshows, and not long before the accident had needed one of the wing skin panels re-rivetting at it had come loose.

The lead technical investigator on the panel identified the cause being a fatigue failure of one of the main wing attachment points near the intake duct and suggested it was the vibrations from the increased airflow of the Conway engines that were the cause. Avro's Vulcan chief test pilot Tony Blackman, who was well aware of the stress cracking issues on the prototype Vulcan wings, also argued that Rolls Royce's maintenance crews were not implementing the extra checks on the leading edge wing structure that Avro had introduced.

H-O-W-L

Quote from: buzby on September 20, 2021, 11:45:33 PM
V-bomber pilots (don't forget the Victor and Valiant squadrons as well) were issued with eyepatches to use on the run-in to the target to try and preserve thier eyesight for as long as possible as the flashes from the first strike attacks were going off. Both pilots would put on their eyepatches, the first flash would blind them both in one eye. The captain would then remove his patch and use his remaining eye. The next flash would blind that eye, so then the copilot would remove his patch and fly using his remaining eye.

However, most of the run-in would be guided by the navigation team (the Nav Plotter and Nav Radar, who sat in the rear crew position alongside the AEO, who took care of communications and defensive countermeasures) via radar, so they had zip-on blackout blinds on the cockpit windows that would only be removed prior to the final stages of the bomb delivery manouver (a variant of toss bombing where the bomb was released in a climb and followed a parabolic trajectory slowed by a parachute, to allow the delivery aircraft a chance to clear the target zone).

Later on, when the difficulty of delivering a freefall bomb against heavily defended targets became apparent, around half of the Vulcan and Victor squadrons changed from delivering the Yellow Sun Mk2 freefall bomb (whixh was a Yellow Sun Mk1 casing with the original British-designed Green Grass warhead replaced with the US-derived Red Snow warhead) to the Blue Steel standoff missile, which also carried the Red Snow warhead and could be released up to 500 miles from it's intended target. Blue Steel was, however, notoriously unreliable, so the crews still trained to be able to drop it as a freefall weapon in the event of a system failure.The flight crews were given no plans for what to do if they survived their attack run. They knew it would be pointless returning home as the UK woudl be glass and cinders by that point, and they didn't have the fuel to do so anyway. They used to joke that in that eventuality best they could hope would be to get as far east as they could and 'marry a plump Mongolian woman and raise a new family'.

Just to add on to this (it's a lot of fantastic information) but this is only wholly the case until about 1980; of course bomber attacks were on their way out as the first-line by then anyway, but flash-resistant PLZT lenses started development by both Western and (as far as we know) Eastern powers by the mid-70s, and were introduced in the US in 1980, though I found it hard to find out when they were truly adopted. They're a specified bit of kit - not something you'd wear on an average flight - but they effectively detect intense light coming into the goggles and dim (or go completely opaque, depending on model/light source) to prevent the pilot going blind.

It's also notable that most expected flight blindness during a nuclear exchange was expected to be temporary, not permanent, as even with freefall bombing the distances would be great enough to prevent permanent blindness (as would the presence of two, three layers of glass, one potentially polarized  between pilot and explosion). The expectation was about eight to ten minutes during daytime runs (when bombing was expected to be done anyway) and ten plus minutes at night.

They also look fucking baller, like something out of a cooler Star Wars:


studpuppet

Quote from: MikeP on September 21, 2021, 03:16:33 AM
Until they broke up...

https://www.youtube.com/watch?v=IYRKFkkyxh0

Par for the course in those days:

https://youtu.be/J89GTFjEH-c?t=96

Sixty-nine years since them slags smashed into the crowd at Farnborough and it still does my nut in.

buzby

Quote from: H-O-W-L on September 21, 2021, 09:43:18 AM
Just to add on to this (it's a lot of fantastic information) but this is only wholly the case until about 1980; of course bomber attacks were on their way out as the first-line by then anyway
The V-Force stood down as the UK's nuclear deterrent in 1970, with Yellow Sun and Blue Steel replaced by the Polaris submarine-launched ICBM. The RAF and Fleet Air Arm maintained a tactical nuclear capability with the new WE.177 weapon system. The Fleet Air Arm stood down it's WE.177s in 1992, the RAF continued it's tactical nuclear role until 1998. In eye protection terms, the RAF evolved to using a gold-plated goggles or visor lens on it's flying helmets, but there were not issued as routine due to the expense.

robhug

on that 9/11 Bin Laden docu that was on I was surprised to learn that Osama decided to attack the US after the disgusting behaviour of the American golfer's during the 1999 ryder cup. He should have made more of that as we could have all got a bit more on board with his reasons rather thinking he was an out and out bad egg.

H-O-W-L

September 21, 2021, 12:18:18 PM #695 Last Edit: September 21, 2021, 03:56:12 PM by H-O-W-L
Quote from: buzby on September 21, 2021, 10:42:27 AM
The V-Force stood down as the UK's nuclear deterrent in 1970, with Yellow Sun and Blue Steel replaced by the Polaris submarine-launched ICBM. The RAF and Fleet Air Arm maintained a tactical nuclear capability with the new WE.177 weapon system. The Fleet Air Arm stood down it's WE.177s in 1992, the RAF continued it's tactical nuclear role until 1998. In eye protection terms, the RAF evolved to using a gold-plated goggles or visor lens on it's flying helmets, but there were not issued as routine due to the expense.

Ah, thanks for the info. I was aware of tests with gold visors in the US (where my knowledge mostly lies, since it's easier to find out about when you're immersed in sources for American military culture as it is) but had no idea about them in the UK.

Infact, belated edit, but my understanding is that gold visors were produced in relatively decent numbers in the US too but they were never used in day to day operations because they could be easily scratched.