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Gaining An R.A.F Pilots Brevet In WW II

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Gaining An R.A.F Pilots Brevet In WW II

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Old 8th Jun 2017, 07:56
  #10821 (permalink)  
 
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I'd just like to thank all those who have explained a lot of the known unknowns (for me at least), be it camouflage schemes or radiator positions for in line engines. The aggressive looking radiator of the Typhoon was a really in your face aspect of an aircraft that could never be termed pretty and was in reality the beast that it appeared to be.

Was not the Sabre in reality two 12 cylinder engines with their twin crankshafts connected at the gearbox? Evidently it had a propensity to catch fire on startup if the priming was not just right (and "right" varied from engine to engine!), and as many fire extinguisher equipped ground crew as possible attended every start up. Thus you kept the canopy open and your straps undone until all 24 cylinders were firing in perfect harmony, ready to shut down and get out pronto if the ground crew indicated that might be a very good idea.

I also seem to remember that mass production of this state of the art power unit posed almost insuperable problems, in particular that of the sleeve valves. Bristol had both the technique and tooling to do so, and had to be ordered to release some of that capability to enable Napiers to ensure any production whatsoever. In the event it was the Bristol radials that reigned supreme, being the last in service UK military high powered piston engines before the ubiquitous jet turbines replaced them all.
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Old 8th Jun 2017, 08:32
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It's fascinating to hear the incredible amount of detail behind the scenes.
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Old 8th Jun 2017, 08:43
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Refering to the leading edge of the Griffon Tempest wings has just jogged a memory. The Provost T!; the real one, not the kiddycar with a vacuum cleaner had strakes just behind the leading edge of the wings on the inboard section. This was to prevent tip stall. It did this by ensuring that the root of the wing stalled first so avoiding a horrendous wing drop if the tip stalled first.

The advent of the swept wing emphasised this because if the tip stalled the centre of lift moved forward and induced a rapid pitchup which made things worse. I remember a film with a F100 dancing along the runway on its afterburner before it ran out of ideas.

The effect was reduced by washout where the angle of incidence reduces along the wing, wing fences, think Mig 15, or notches to prevent outward flow which would do the same thing.
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Old 8th Jun 2017, 09:05
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Roland Beamont on the Tempest...
"Reaching Newchurch airfield at 480 mph I held "RB" down to 20 ft from the runway and then pulled her up to a 60 ° climb holding it as the speed dropped slowly off and the altimeter needle spun round the dial as if it were mad. At 7000 ft the speed was dropping below 180 mph and I rolled the Tempest lazily inverted, then allowed the nose to drop until the horizon, at first above my head, disappeared below (or rather above) the now inverted nose, the fields and woods steadied into the centre of the windscreen and then whirled around as I put the stick hard over and rolled around the vertical dive. Steadying again I pulled out over the tree tops at 500 mph, throttled back and pulled hard over towards the airfield in an over-the-vertical climbing turn, lowering the wheels and flaps in a roll as the speed dropped. What a magnificent aeroplane! They could have all their Spitfires and Mustangs!"
("My part of the sky", Roland Beamont)
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Old 8th Jun 2017, 10:43
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DHfan (#10821),

...."Re Fareastdrivers comments on the Centaurus and Sabre. According to Wiki, and I'm pretty sure I've previously read it elsewhere, an experimental Sabre produced 5,500 hp on test. That's spectacular from 37 litres"...

Puts the Wright Double Cyclone (2600 cu in) in the shade: 1,600 hp from 42.6 litres. And the Merlin 266 produced the same 1600 from only 27 litres !

The payoff was legendary reliability, as it was so lightly stressed.
 
Old 8th Jun 2017, 13:36
  #10826 (permalink)  
 
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Think you've got the nub of it there, Danny. Though not such a marked difference to the contrasting engines that you instance, the Hercules 216 engines (1800 bhp) of the Hastings were extremely reliable. I experienced only one shut down in anger while operating them, and that was due to the failure of an external oil pipe rather than of the engine itself. Its big brother though, the Centaurus, was rather less reliable. As fitted to the Beverley, the 173 variant (2850 bhp) always had a prodigious thirst for oil.

There proved to be a slight snag in Court Line's cunning plan when they obtained a Beverley and put it on the UK register, as it was then the only UK aircraft capable of carrying an RR RB211 internally, in order to enable a quick reaction engine change down route for its two L-1011 TriStars. The slight snag being that the Beverley's Centaurus engines proved to be more unreliable than the RB211s it was meant to shift!
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Old 8th Jun 2017, 14:00
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You might be interested in the following. The year is 1950:

"Engine failures were still happening frequently. Strange as it might seem nowadays, the Hastings force at this time used re-cycled oil in its engines. An Oil-Cooler Flushing Unit was set up at Lyneham and the engine oil-coolers were fitted with back-pressure gauges. When the back-pressure reached a certain value, the cooler needed flushing. This was fine if the aircraft was at Lyneham but not quite so handy if it happened to be at Mauripur.

The oil-cooler shutters were also inefficient and "coring" was a common occurrence. This phenomenon was caused by the cooler getting too cold which allowed the oil in contact with the matrix to solidify. This drastically cut the flow of oil passing through the cooler, rather like a mechanical version of the narrowing of the human arteries. Consequently the temperature of the remaining oil flow escalated to dangerous levels. Coring was fairly common when the aircraft was forced to climb into cold air, such as was necessary to cross over the Massif in France, for example. Eventually, new oil-shutter seals were developed and this helped ease the problem enormously, but not before the Hastings had become known as the finest three-engined transport in the RAF!"

I find it quite mind-boggling that they even tried to use re-cycled oil.
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Old 8th Jun 2017, 14:24
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20 ft from the runway and then pulled her up to a 60 ° climb holding it as the speed dropped slowly off and the altimeter needle spun round the dial as if it were mad. At 7000 ft the speed was dropping below 180 mph and I rolled the Tempest lazily inverted, then allowed the nose to drop until the horizon, at first above my head, disappeared below (or rather above) the now inverted nose, the fields and woods steadied into the centre of the windscreen and then whirled around as I put the stick hard over and rolled around the vertical dive. Steadying again I pulled out over the tree tops at 500 mph,
When on Vampires at Oakington I had a girlfriend that lived on the outskirts of Wem. A similar flight profile but I failed to notice a series of long sheds with hoppers on the end.

Apparently USAF paid for about 2,000 chickens because she persuaded the farmer that I had Stars on the Wings.
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Old 8th Jun 2017, 14:56
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JW411:-
I find it quite mind-boggling that they even tried to use re-cycled oil.
Quite agree. Ancient as I am even 1950 was before my RAF career, and the Hastings 1's were powered by Hercules 106 engines (1675 bhp) then, for what that's worth. I can't tell you what I've just come upstairs for, but the words coring, sludging, and Solomon Dampers will remain with me to the very end.

Our Flight Engineers (for whom we give thanks to the good Lord) were very much on top of such nasties as you describe and I do not remember any incident of either malady, so Mr Solomon's dampers went on turning, doing whatever it is that they did (damping?).

As far as I know all our POL's were fresh out of the tin, and such nasty dollar saving practices as recycling them for reuse were things very much of the past.
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Old 8th Jun 2017, 15:33
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My late father was on 202 Sqn Hastings maintenance 1954-1964 and said the Hercules reliability was much appreciated on 8-10 hour Atlantic met flights. All sleeve valve engines drank oil but Aldergrove's was certainly not recycled. Indeed, it was not unknown for a tin or two of delicious OMD-270 to find its way into our ancient Hillman Minx
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Old 8th Jun 2017, 16:13
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While I was digging out the bit about the Hastings oil problems, I came across another 1950 Hastings story in my book which I think shows absolutely magnificent flying by some very brave people:

"It had been decided to shut down the Singapore slip schedule for Christmas so Hastings TG574 was sent off to act as the "sweeper". It had already "swept-up" four complete slip crews and three passengers on its way from Singapore through Negombo, Karachi and Habbaniya when F/L Graham Tunnadine and crew (of 53 Sqn) climbed on board at Fayid on 20 December. They had hoped to make their next refuelling stop at Castel Benito but had to make an unscheduled stop at El Adem. They finally left El Adem at 1958 and set course for Castel Benito climbing up to 8,500 feet before setting cruise power. The co-pilot, F/L S L Bennett, went back to rest on the crew bunk since he was expected to fly the aircraft on to UK from Castel Benito. His place on the flight deck was taken by S/L W G James of 99 Squadron.

Some 42 minutes after take-off, at 3205N 2120E, there was a loud bang and a great deal of violent shuddering. A blade had come off of No.2 propeller and had sliced through the fuselage, severing all of the tail control rods. It had then struck F/L Bennett, who was resting on the bunk and had taken his right arm off. The three remaining blades on the No.2 propeller were now hopelessly out of balance so the entire engine was torn from its mountings and fell off, taking the port undercarriage and a large section of the wing leading edge with it.

Graham Tunnadine was desperately trying to keep the aircraft flying straight and level but had an almost impossible task on his hands. The flight engineer, Sgt P E Walker, had quickly established that there was no hope of repairing the severed tail control rods so the only primary flying controls left undamaged were the ailerons. First of all, the captain had to prevent the nose from getting too high otherwise the resulting stall would be impossible to recover from. He tried having the movable baggage and equipment in the cabin moved forward but there wasn't enough of it to have the desired effect. Next, he got the slip-crews to move fore and aft until the aircraft was flying level.

He was then able to keep the aircraft reasonably straight by using the ailerons and asymmetric thrust from the remaining three engines. Just how long the engines could put up with this sort of punishment was another question. The signaller, Sgt G J Bain, had sent out a Mayday call which was answered by Benina, the RAF airfield near Benghazi. Although they were not expecting any aircraft that night, they told Sgt Bain that they would quickly lay out a flare path and provide fire equipment and medical services, so it was decided to attempt a landing there.

S/L T C L Brown, a senior medical officer from Abingdon who was travelling as a passenger on TG574, had immediately gone forward to look after F/L Bennett. He tried to move him from the wrecked bunk area but found that he was trapped by wreckage. He made the brave decision to stay with the seriously injured co-pilot, fully realising that he would be in great danger when the Hastings crash-landed.

F/L Tunnadine had eased the aircraft down to 6,000 feet by the time they arrived overhead Benina and his plan was to do a belly-landing by putting power on at the last moment in the hope that this would be enough to raise the nose. He then descended to 1,000 feet by moving the slip-crews around again and positioned the aircraft on to final approach. Two slip-crew members stayed on their feet in order to make last-minute trim changes before diving into the nearest seats just before impact.

They almost made it to the airfield but TG574 struck gently rising ground just a few hundred yards short of the runway. The aircraft bounced for another 100 yards, the starboard wing struck the ground and the Hastings ended up on its back at 2155. Thanks to the use of rearward-facing passenger seats, everyone in the cabin survived with only minor injuries. It was a different story at the front of the aircraft. The nose was smashed in and F/L Tunnadine, S/L James and the navigator, F/S I A Johns, were dead. Sgt G J Bain was seriously injured and died on 24 December. Sgt Walker and the AQM, Sgt W A Slaughter were injured.

Sadly, F/L Bennett had died of his injuries and S/L Brown, who had bravely sat on the floor holding him in his arms, was seriously injured. He was happily to recover and was awarded the George Medal. The crew of TG574 were each awarded the King's Commendation for Valuable Service in the Air. Many at the time considered this to be miserly recognition for such a magnificent piece of flying".

When I found this story I was really quite moved. I was serving with 53 Sqn on the Belfast at the time. By something of a coincidence, one of the slip-crew navigators on TG574 (S/L I R L Jones) was also serving on the squadron so I was able to get a horse's mouth account of the whole event. He told me that thanks to his rearward facing seat, he was completely unhurt and, within 15 minutes of the crash, he was helping out by driving an ambulance!

I wonder how many of the youngsters nowadays could achieve what Tunnadine and his crew did?
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Old 8th Jun 2017, 16:21
  #10832 (permalink)  
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JW411 and Chugalug,

I didn't think that anyone would be daft enough to run aero engines on recycled oil, but remember all too well that in the new-car famine years after the war our ancient 'bangers' had enormous appetites for the stuff.

As late as 1954, I'd bought a 1938 Vauxhall 12-6 which ran through a sump-full every 100 miles (and you couldn't see out of the back window for smoke). Any country garage would sell you "reclaimed" (ie filtered through a bit of newspaper) sump oil for a shilling a quart.

Imminent matrimony obliged me to have the engine fettled before the great day; it took us on honeymoon and faithfully served us for five more years before a posting to RAF(G), and a generous Bank manager, allowed us to realise our dream of the First New Car - the Peugeot 403 of which I have written in such glowing terms.

I look at road traffic now, and see few damaged cars, no rusty cars, no smoky cars, hardly any dirty cars - but some of the fun has gone out of the business (how long is it since you "got out and got under" ?)

I've been told that airlines use remould tyres (is that true ?), but I don't think they would descend to the desperate expedient of a "recut". (What was a "recut", Grandad ?) ... Well, when you'd worn all the pattern off your tyres so that they were smooth as a baby's bottom, road holding in the wet was problematical. Some unscrupulous character would cut you a new pattern in the tissue thin rubber, just stopping before the canvas showed. You could get a few hundred miles before the blow-out (if lucky).

The incredible thing is: your young damsel would happily nip into the passenger seat without a care in the world (and their mothers would let 'em !)

Keep Death off the Road ?

Danny.
 
Old 8th Jun 2017, 16:29
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and said the Hercules reliability was much appreciated on 8-10 hour Atlantic met flights
When I was at Aldergrove the Bismuth flights would normally land back with just three engines. My father got the AFC after he had recovered a Halifax to Shannon after losing two over the mid Atlantic.

I remember that Hastings story in the fifties. Whilst I was training in the Provost T1 I was always wary when an aircraft taxied past me as the propeller plane passed my position.

An ex Panam Constellation had a similar problem abeam Belize where No 3 threw a propeller blade and the engine rotated into the wheel bay. No 4 received the debris and caught fire. It eventually landed with No 4 on fire on just the starboard main and nosewheel.

The captain was in tears; he had done a lot of time in it with Panam.

I've been told that airlines use remould tyres
They do. I believe that, on condition they are good for four remoulds. There was a standing joke that when they passed that limit Air India would buy them and get three more remoulds out of them.

I don't think that that was true.

Last edited by Fareastdriver; 8th Jun 2017 at 16:39.
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Old 8th Jun 2017, 16:35
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I can assure you that airlines do indeed use remould tyres. Mind you, they are done to a much higher standard than the remoulds I used to put on my old Riley Falcon. In 32 years of civilian flying I never had one let me down.
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Old 8th Jun 2017, 17:25
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Yes Chugalug the Hercules/Hastings combination was eventually very reliable but only after a very troublesome time earlier in its life with the Herc 100 as fitted to the Mk 1, indeed the term “consumable payload” was allegedly invented to describe its very uncertain reliability during the 1949-50 period. Allegedly on at least one occasion a Hastings departing Lyneham loaded with three spare power units intended for stranded aircraft never reached Changi, having to use up its own payload to keep itself going!

JW411, I recall the Benina accident well having just been posted to 99 Sqdn following withdrawal of the York from service. Such recognition as the crew received was (in the opinion of many) indeed derisory and inexcusable, especially in the case of the captain who did a brilliant job - a posthumous AFC would have been more appropriate.

Reference has been made to the inordinate thirst of sleeve valve engines, often measured (especially for the Centaurus) in several gallons per hour. On the other hand, in my experience on both Hastings and Beverely they were pretty reliable – indeed I don't recall ever having an in-flight failure during my (admittedly) fairly limited time with the Bev, other of course than the episode recently described in #10757 – which was no fault of the engines themselves!

Mention of the Bev reminds me that perhaps another reminiscence is due, so read on where I attempt to describe in a light-hearted way some of its peculiarities as experienced by its users – both crew and pax:


Despite its many virtues even the Beverley's most fervent aficionados would hardly claim speed as one of them, however reports of trains overtaking it can possibly be discounted although an encounter with to-day's TGV or equivalent would be a different story. Short hauls were no hardship, but of necessity it had frequently to undertake long-range flights; that many of these derived from the RAF's absurd attempts to use it as a Hastings replacement, was of little consolation to those who had to endure hours of mind-numbing boredom as a result.

For the pilots tedium was initially alleviated by the need for hand-flying, no autopilot being fitted until fairly late in its life while at the same time lack of a flight engineer involved them in routine duties (i.e fuel system management, logging engine readings etc) normally carried out by this functionary - after all, was the bird not designed for short-range work (pity no-one told Upavon, though). As for other crew members, the navigation & radio empires were adept at keeping their members busy, often with less than essential tasks, while running up and down ladders with trays of refreshment kept the quartermaster fit & alert - hot climate operations in particular saw to that, but what of the wretched customers?

Sleep is of course the best way of passing air time but even the most noddy-inclined individual has certain limits in that field, so what other recreation was available? Passengers were normally carried in the boom compartment, which provided some relief from the noise but offered a very poor view out from the slightly upward-sloping windows; so, to see whatever was on offer from the main deck, it was first necessary to scramble awkwardly down into the hold, using the stringers as a step-ladder.

Primarily intended for freight, its generous 10' x 10' x 40' capacity nevertheless provided ample space for passengers where they would endure a decibel level way beyond any sensible limit – although carriage of motor vehicles (especially private cars carried as indulgence freight on homebound flights) could offer some escape from the interminable din. Slipping inside with a good book, one could read for hours in greater comfort than was possible in some contemporary airliners. Unfortunately however, any encounter with turbulence, always likely at the Bev's comparatively low operating altitude, necessitated a rapid evacuation if nausea were to be avoided; vehicle suspensions are designed to deal with surface irregularities, but merely exaggerate the effects of rough air. Keeping the pax warm was less of a problem than might be imagined, for the Bev was fitted with a number of combustion heaters providing hot air for both cabin and de-icing; burning avgas supplied from the aircraft's fuel system, they were at first regarded with some suspicion but in practice were reasonably reliable and to the best of my knowledge never caused any serious incident.

Should the hold be empty, athletically inclined persons could jog to & fro. Noticing a bicycle lashed to the cabin wall on one occasion, I rode it in a figure eight pattern for about five minutes (perhaps setting some kind of record, cycling over France at 150 mph?), though it was rumoured that someone once actually did the same on a motor bike! Then there was the supply aimer's position in the nose, giving a superb view of the passing scene through its clear glass panel. I spent some hours thus, and during one clear passage over the Massif Central was able to garner much useful data towards the planning of a forthcoming French holiday.

We all remember the Centaurus engine's voracious thirst for oil, so that during the longer "drags" it was usually necessary to hand-pump this commodity from the reserve tank to the engines - a task accomplished in a noisome hole in rear of the flight deck, where both temperature and decibel readings were normally off-scale. It was an exhausting chore, rendered worse by the impossibility of using oxygen in an oily environment. Visitors to the flight deck were encouraged, in the sly hope that they might be conned into becoming oil pumpers; sometimes the ruse was successful, but they were seldom "had" a second time. Why an electric pump could not have been provided (with the hand pump as a back-up) is another of those little Beverley mysteries - along with the lack of a galley, no autopilot etc etc.

No doubt human ingenuity dreamed up other ways of passing the hours, for there was always time to spare on a Beverley flight!
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Old 8th Jun 2017, 18:02
  #10836 (permalink)  
 
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JW411, thank you for telling the story of TG574, and of the terrible accident that befell it, the crew, and its passengers. As FED reminds us, any propeller driven aircraft (especially the multis with wing mounted engines) had the potential to fling large chunks of fast rotating metal into the fuselage, the wings, and adjacent engines. Even FED's beloved Piston Provosts held a similar threat to life and limb, as he says (funny you should have likened the JP engine to a vacuum cleaner, for it always reminded me of such when opening the bay access panel above it. There, in a space that would have easily accommodated an engine two or three times its size, was the tiny AS Viper that looked more like a Goblin cylinder).

Danny, absolutely agree about the Griffin Spits, it just made a beautiful classic aircraft into a beautiful and potent classical aircraft. By coincidence this month's Airfix wallpaper is PS852, a Mk19 PR Spit. It might just have to stay there into next month as well!

https://www.airfix.com/uk-en/downloa.../index/cat/39/
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Old 8th Jun 2017, 19:18
  #10837 (permalink)  
 
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I have read that the Spitfire's major limitation was its c of g limitations which inter alia precluded extra fuel tankage. I have also read that great care must be taken on runup because if the tail begins to rise the limited prop clearance and high polar moment produces an inevitable strike no matter how quickly the throttle is closed.

A good friend and the man who introduced me to airways flying with a trip from Belfast to Bremen in my Arrow, Allan Deacon joined Shorts as a test pilot after a period with Rolls-Royce during which he flew the RR Spitfire XIV which I think is the one in these pictures, and borrowed it (yes, a Spitfire!) for our air display about 35 years ago.

At that time I was de facto airfield manager (which involved clearing up, driving digger and mower etc) and went ballistic when I spotted a line of slashes down our new runway surface. Who the ****** drove a tracked machine down the runway, I demanded. Turns out that Allan to his great mortification had tipped the Spitfire prop when he opened up on takeoff, each slash being the tip of its five-bladed prop.

Engineers came from RR and declared it fit to fly home for repairs. Poor Allan was drowned after baling out from a Tucano which broke up during test flight over the North Channel.
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Old 8th Jun 2017, 21:22
  #10838 (permalink)  
 
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Originally Posted by Chugalug2
Was not the Sabre in reality two 12 cylinder engines with their twin crankshafts connected at the gearbox?
Yes, and er... no. That would be far too simple.
The propeller drive was actually taken from the ends of the four camshafts, which was either barking mad or a stroke of genius.
Personally I think it was very clever. The camshafts run at half crank speed so there's the first part of the reduction gearing and then there are four well-spaced gears transferring power to the output gear rather than the usual one.
Unlike the Merlin where the prop runs at around half engine speed, the Sabre's more like a quarter in round numbers. I imagine a standard reduction gear design would have been massive.

The Bristol engines did last longest but Sabres were in service surprisingly late until 1955 in Tempest target tugs.
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Old 8th Jun 2017, 21:35
  #10839 (permalink)  
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JW411 (#10832),

What a horrible story - and what a good job they did in the circumstances ! (why didn't that doc get an AFC - do you have to be aircrew ?) Failing that, they should've made it a G.C. Vaguely recalls that US story of a DC-10 where the tail turbine wheel broke off and severed all the tail control connections. He flew it to Salt Lake City (?) by juggling the two good engines and crash-landed it on the runway, many killed but a fair number survived (inc the pilots). At the next harvest some farmer found the turbine wheel in his corn.

FED (#834),

A JP at Leeming lined up for t/o and opened up. Viper turbine stripped, all the shrapnel sprayed out evenly and pretty well bisected the JP. No casualty.

One day a Percival Pembroke took off from Catterick (with CinC Maintenace (?) Command on board), climbing S. (in our direction). Loud Bang, a whole pot blew off and went through the cabin wall, across the cabin and out the far side. Did not hit anybody. They feathered and went straight on to land on Leeming's 16.


Chugalug (#10837),

Thanks for the link - fine pic of the Griffon Spit. As for JPs, spent five years looking at them out of the tower window, but never even bothered to look into the cockpit. I'd had my flying years, and they were good years, but now they were over.


Geri (#10838), and others,

Yes, you had to be careful on take-off with any Spit, and hold the nose up a bit to keep the prop tips off the ground. In consequence it floated off by itself like a TM.

My thanks to all who've confirmed that remoulds were in fact used.

Cheers all, Danny.
 
Old 9th Jun 2017, 07:14
  #10840 (permalink)  
 
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DHfan, once again you add to my (our?) education. As you say, taking four drives off of the camshafts gave an immediate speed reduction as well as a more stable one. The sheer compactness of the Sabre can be seen from FED's pic of it. I must admit that I tend to characterise such cutaways as a "suitable arrangement of cogs and levers " so missed the design features that you point out.

It all rather reminds me of a "pilots watch" that my wife bought for me in Switzerland (no, not the 'B one!). Other than gently pointing out that the last place to buy a Swiss watch should be Switzerland, I also rather ungenerously queried what made a watch a pilots watch, other than that it should keep accurate time? When the interior arrangement of cogs and levers refused to operate further I took it to a watch repairer. He managed to get it working again but made the observation that, "this watch is too clever for its own good". Perhaps the same might be said of the Sabre?
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