TempestNutTotal Merlin production amounted to about 155,000 engines, with Packard producing 55,000, or so. In the west the Merlin comes 2nd to the R 1830. Nothing else comes close. Remember that the B24 was the most produced US aircraft of WWII and it had 4 R1830s. Add in all the C47s with 2 and those 2 aircraft alone account for a huge number of engines.
TempestNut[QUOTE=XN923]I think Sydney Camm wanted to put the radiator in the wing root from the very beginning, but there was a suspicion that this would be vulnerable (not sure to what – gunfire perhaps, but also maybe plumbing issues). He also designed a version of the Tempest (the Mk1 I think) with this layout, and of course the radial engined versions all had the radiator in the wing root as did the Sea Fury.
The wing-root rads on the Tempest took up space that was better used for fuel, and the speed advantage of the MK1 over the production MkV was at higher altitude, and less obvious lower down where it was envisioned that the Tempest would spend most of its time. I think this factor more than any worry about vulnerability was the practical driving force that produced the decision to produce the MKV.
Tanks were put in the wings and with a pair of 45 gal drop tanks the Tempest was able to provide escort to the Ruhr and back from the UK, further than the P47 with 100gal tank. With the later 90 gal tanks the Tempest V could have provided excellent escort to bombers from England. But remember that the Tempest as it was, was peerless at Battle Field air superiority and this was where it was mostly used. Nothing then in production and prop powered was faster below 5,000ft.
Wing-root rads made a come back with the Fury prototype powered by the last of the Sabres. This was the fastest piston pwered Hawker Fighter with a speed of 480mph I think. Presumably they had solved the fuel tank issues as the Sea Fury had wing-root intakes for the engine on both sides and an oil cooler on the port side, as did the Sabre powered F6
TempestNutAh diesels. It may come as a surprise to everyone but the Shackleton was to be Diesel powered with the exquisite Napier Nomad. This engine was a 12 cylinder horizontally opposed 2 stroke engine, turbo supercharged and using a axial flow power recovery turbine to harness the high exhaust energy inherent in the 2 stroke design and drive one half of the contra rotating prop. The benefit of this beast promised to be unprecedented fuel economy for long endurance in the intend role of the aircraft. Unfortunately, Napier’s ambitions where ahead of their ability to develop the technologies in a timely manner, and the Shack ended up with the safe option of Griffons. Shades of the Sabre. The Nomad was not at all similar to the Junkers engines, or the Deltic that powered trains and boats, but was similar to a Detroit Diesel, or as they were called during the war GM Diesels
TempestNutWhat a hideously complex arrangement that engine is – 3 crankshafts and pistons flying every which way. Horrible waste of space in the middle too. I doubt it if helped with cooling.
Can someone explain (in laymans terms) what advantages the Deltic held?
In simple layman’s terms the advantage was simplicity and power density. The Deltic was an opposed piston 2 stroke diesel. These engines have no valves and rely on a supercharger to scavenge the cylinder via ports in the cylinder wall, a bit like a sleeve valve engine. If any of you are old enough you may remember the Commer diesel trucks. They had 3 cylinder versions of the Deltic.
Each Deltic cylinder is roughly equivalent to 2 normal 4 stroke cylinders. As each of the Deltic’s 3 banks is 6 cylinders, it’s the equivalent of 3 V12s or a boxer 12s and you could say the Deltic was a 36 cylinder engine that could fit into the same space as an engine of half its power.
TempestNutInterestingly, for some at least, 487’s original compliment of aircraft were painted in the day fighter scheme and not as nearly all subsequent mossie fighters in the night-fighter scheme. EG-T ( MM417 ) is one of these early aircraft. Apparently the pilots reported that the scheme was too visible, and preferred the night fighter scheme of medium sea grey all over with a disruptive pattern of green on the upper surfaces. 487 was one of the original FB6 squadrons having reluctantly been asked to give up the Ventura.
TempestNutI saw Ray and Stefan flying Spencer Flacks SpitXIV and Hunter respectively at Biggin Hill in I think 1980. Ray came down from altitude to open the display in his favoured banked curved entry from behind the crowds right, then down on into the valley. It was very fast and spectacular and had the crowd oohing aahing. This was quickly followed by Stefan in the Hunter, going very very fast so we saw him and then heard him. He had throttled back just before reaching the crowed so the sound was more an eerie swishing than a jet roar. Of course the Hunter at speed could not disappear into the valley the same manner as the spitfire but the commentator was moved to say “Um that looked at little like anything you can do, I can do better” accompanied by much chuckling.
I was able to quickly ask Ray at the OFMC Tiger convention in 2004 if he remembered that display and flying the SpitXIV. He winked at me and with a twinkle in his eye said “we could do a bit more in those days couldn’t we” It was the first time I had seen a Spitfire flying, and I got a real treat seeing the great man fly 2 of them.
TempestNutI agree. Remember an angry mind is not a clear mind.
Sadly we live in a world full of NIMBYs (look at Stansted) and it certainly looks as though we have one here. .
Err be very careful when using Stansted as an example. I live in the area and the BAA’s plans where/are grotesque to say the least. They took no account of transport, the current shortage of water in the area, new homes, schools and hospitals. I oppose the expansion because of a lack of these services first and foremost. Join up the thinking and I’m sure progress can be made here. In many ways expansion in Stansted will be good, but not without many other improvements. Its in the interests of the whole country that Stansted is done properly.
Rant over
TempestNutOh no, what a shock. I can’t believe it. My sincerest condolences to Rays family and friends. I first saw Ray fly at Biggin in 1980, and the last display for me was FL this year. 25 years of entertainment and excitement. Ray you were the best RIP
TempestNutIf you fired the NOx at sea level then you would get a power boost over and above the rated output, but it was obviously used, much in the same vein as a Super/turbo charger to give back some of the tail-off of power at altitude.
There is a view that using NOx isn’t too detrimental as the cooling effect offsets the additional heat created, but the strain on the reciprocating parts must be taken into account.
I am mystified why the ‘Compound’ engine didn’t really get developed, where the exhaust gases are passed through an impellor directly attached to the Crankshaft (a la Constellation)
Compound engines are excellent for continuous power for example an airliner or bomber, but less useful when numerous throttle movements would be necessary, as in a fighter. This is demonstrated with the US army air force bombers Vs US navy fighters. The Army wanted to use the Turbo supercharger on all its aircraft, and all the heavy bombers were thus equipped and performed very well. The compound engine was an extension of this technology, but was not sufficiently developed and therefore not available during the war and was overtaken by the turbine engine, again a further development of similar technology.
US fighters with the turbo supercharger were far less successful, until employed in roles other that that for which they were originally intended. The P38 is the best example of this, performing better at low altitude in the fighter bomber role than as a high altitude interceptor. The P47 was more successful at altitude but was again better employed as a FB. The US navy developed two stage superchargers in a parallel to the developments at RR and the Hellcat and Corsair were very successful in their intended roles, despite using the same basic engine as the P47. Horses for courses as they say.
Another point to remember is the contribution of the exhausts to top speed in a fighter. In a turbo supercharged engine some of the exhaust energy is recovered via a turbine. In a full mechanically supercharged engine in a fighter the exhaust energy was used as jet thrust. On a Merlin at full chat and at 400mph this could be in the region of 300hp. This is a lot of power to dispense with for a recovery turbine that out of design necessity had to be optimised for either cruise economy or full power
TempestNutNitrous is an oxidising agent, but it also cools the mixture and it enables you to inject an extra shot of fuel. I don´t see why you would say that it wouldn´t increase power?
James, I’m not saying it wouldn’t under certain conditions, but if the Merlin 23 for example had a maximum rating of 1400hp @ 3000rpm at say 18,000 feet in hi blower, it would be limited to this power by the mechanical integrity of the engine components. This same engine would only produce maybe 650 hp @ 30,000 ft at the same max full throttle settings. Using NOx under these conditions would allow the engine to produce say 1000hp, by supplying additional oxygen. (1000hp @ 30,000ft was the target hp for the Merlin 60, the first of the two stage engines.) At no point would NOx be used below rated altitude to increase the max hp above that to which the engine is mechanically limited.
The Merlin 25 had a higher std rating of about 1650hp, at a lower rated altitude of 14 to 15,000ft. What’s more it had components that allowed short bursts of power at much higher boost pressures. However this extra power was most often used, and far more effective at low altitude, well below the rated altitude, and usually limited to low blower to reduce parasitic loses. ADI (water/methanol) would have been manner from heaven in these situations, but NOx was completely unnecessary as there was always enough Oxygen present below 10,000ft.
I hope this clarifies matters. By the way my figures are approximate and not exact, but close enough to illustrate the point. ADI was developed for the Merlin, but as the 2 stage Merlin 66 could run at @25lb boost and 2000+ hp, it was seen as unnecessary at the time. The Merlin had been cleared to run at 30lbs and 2200hp prior to the end of the war, and ADI had been developed to take it further still. Now it’s the racers of Reno that take advantage of all this good work.
TempestNutI think you will find that the Nitrous Oxide was to basically add extra oxygen to the engine above the rated altitude of the single stage Merlin’s then fitted to the fighter Mosquito’s, pending the arrival of the Mk30 with two stage engines. At no time would the engines have produced additional power over and above the rated power for the particular engine model. MkXIII, were produced with both Merlin 23’s and 25’s, the later capable of running a higher boost. I haven’t got my references with me but I think that the 23s maxed out at 16lbs (or 14lbs) boost and the 25 at 18lbs. Some 25s were modified to run at 20 plus lbs for chasing V1s, but I’m not sure what the exact maximum was.
TempestNutA goodly number of great pictures have been posted over the last few days. So a little bit more nostalgia.
I have taken DHFAN’s advice and posted these as jpegs so they should load faster.
1 Noratlass 172 coded 61-NV
2 T-33A 51-4415 coded TR-415 (was in scrapyard at Lasham 09/67)
3 C-141A Starlifter
4 B-66 Destroyer 54-0520 coded BB-520
5 RF-101G Voodoo 54-1455
6 C-54E-15-DO Skymaster 44-9146
If the C141 is parked beside a NAC DC3 then it must be the Opening of Auckland International Airport in the southern suburb of Mangare about January 29th to 31st 1966. Shame I didn’t have a camera then, but that Starlifter put on what seemed to me as a young boy an unbelievable display. I recall that the take off and climb seemed to be at an impossibly steep angle and the size of it dwarfed everything else at the show. By the way my other abiding memory of the show was how noisy the BAC111 was.
Funny thing is I can not remember much else from that show, one of the first I went to. I know there were Harvard’s, Vampires and Canberra’s of the RNZAF, along with Bristol Freighters and maybe the Hastings were still about too. However I do recall the Hercules putting on a show to match the Starlifter but it could have been a US aircraft. Maybe someone has a list of what was at that show. It would be 1980 at Biggin Hill before I would see an other gathering of aircraft to match that of the Auckland opening.
TempestNutAh right, I’m having a look at Nikon’s site right now…what Nikon product do you recommend – like the D70 or D100?
Try this chart http://www.nikonians.org/html/resources/nikon_articles/body/chart/nikon_dslr_chart.html
I would say the D70 is your best bet, with D50 if you want to spend more on Lenses
TempestNutThank you mate, that’s great 🙂 – I’ll go and do a good bit of research into that. The only reason that I was specifically looking at the Canon range is that I know their cameras all are of excellent quality and are good feature wise, however it does pay to shop around. I’ll have a better look at Nikon and Olympus. What about Kodak?
Kodak make sensors and camera’s, but have just pulled the plug on their Hi end pro model DSLR. And they don’t make lenses. So its a matter of watch this space for them. For example whilst Olympus is relatively small in DSLR camera’s at present they are large in optics in other fields, so have vast experience making lenses for astrophysics and medical equipment. This is why their lenses are so good. Some are very expensive also!!!!!
TempestNutJamie, as you are starting from scratch, you have the DSLR word at your feet and the opportunity to buy into a designed for digital system and not invest in a system that relies essentially on legacy designed for film lenses. Before you buy anything, check out the New Olympus E500. This camera is priced in the EOS 350D Nikon D50 range but has the features of the 20D. Not only this, but the Olympus kit lens are far and away the best on the market, and the build quality is second to none. Just ask the shops how many come back for repair. Also the Olympus JPEG engine is reputedly the best on the market bar none, and this is important for beginners who are not necessarily set up to convert from RAW files themselves.
The 4-3rds system that Olympus has designed is the only DSLR system that has been designed for digital and this means you are investing in a system that will still be able to take advantage of greater resolution of digital sensors that will be around in 10 to 15 years. Most legacy film lenses are now at the limit of what they can produce with 6 to 8 Mega pixel sensors, and this will severely limit your expectations further down the line assuming you wish to take your photography on, and emulate some of those who post on this forum. Another factor to bear in mind is that if you wish to branch out into other areas of photography and take advantage of wide angle lenses on reduced frame senor camera’s at reasonable prices then you will find that Olympus is currently the only manufacturer that can offer quality wide angle lenses at reasonable price. Also the Olympus DSLR’s are the only cameras with self cleaning sensors.
The Current twin lens kit from Olympus of E500 and (14-45mm + 40-150) is outstanding value for money and comes within your budget. Nowhere else will you get such value. You will note that the focal length of these lenses produces a field of view equivalent to twice the focal length, so a 150 is like 300. Combine this with the 1.4 converter and you have 420 with no loss of quality. Or try the single lens kit, (14-45mm) and buy the outstanding 50-200 that will give 400mm, or 560mm equivalent field of view in combination with the 1.4 converter. One area where a Canon has a clear advantage over Olympus is in hight ISO noise levels. However I don’t think this is as a pronounced as is often made out and The E500 appears to be an improvement over the previous E300.
Camera bodies are being upgraded/ replaced every two or three years currently, if not more often and it is better to put your money into quality glass, than it is to spend on bodies and cheep glass. Canon and Nikon base their reputations on their professional range of cameras and lenses which are fantastic. But it is not often realised that especially in the case of Canon that these camera’s use full frame sensors and require only the very best of lenses to give acceptable results. Consumer quality lenses are often hopeless on these cameras, EOS 1Ds 5D etc whilst giving acceptable results on reduced frame sensor camera’s EOS 20D, 10D 300D 350D. So, whilst the growth path may look clear, it is often quite blurred.
Panasonic is due to release a DSLR body next year, possibly at PMA, in February 2006, that will be compatible with the four thirds system, where all bodies and lens built to this standard are completely interchangeable. This will improve the choice you will have going forward and if you look at how Panasonic has revolutionised the camcorder field, then you have to assume that they would not invest in a system that does not have a big future. Checkout the following links and visits the various forums. It’s very enlightening, and will help you make your decisions that you will be able to live with for years to come.
One last point, don’t get hung up on mega pixels, anywhere from 5 to 8 will do, and 8 is not necessarily better than 5 on all camera’s. It’s the quality of the pixels that matter.
http://www.4-3system.com/ This site is a good site for all that is available in the 4/3rds system. Read it all and get a sence of how the system has been developed
http://www.dpreview.com/ this sight is good for camera reviews and the forums will give you an insight into reliability. I urge you to check them out.
http://www.myfourthirds.com/ This sight for images taken by ordinary photographers like you and me that demonstrates the superiority and potential of the fourthirds system.
I myself got my first Olympus camera an OM1 in 1973 during my last year of school, and was recommended it by a school mate who had his dad’s Nikon F1 to use. I was the envy of my class. I followed up with an OM2 in 1980, and an OM4 in 1984, along with 7 lenses and have never had to have any repairs done other than one lens checked out after it was dropped. (cost me £35). This is a record not match by my friends who followed the flow and bought other makes based on marketing hype and share. I’m currently awaiting the new E3(?) due out next year.
Jamie I hope this helps and as you have some time on your hands I urge you to do the research and not jump too soon. It would pay you check out Nikon carefully as well, as they also produce outstanding camera’s. A choice from 3 makes is going to make you more comfortable than a choice of 3 models from one manufacturer.
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