restored out of necessity...Short Solent

[harrysone]

I have copies of basic 3-view drawings that were in TEAL Solent's flying notes...I can scan these and post, pretty sure it shows the engines in line with slipstream

[Dave Homewood]

Really interesting David.

[davidd]

What is really required are plan-view photographs, drawings are often simplified. There are some great ones of RNZAF Sunderlands at air displays, etc, showing very clearly the canting out engines, but cannot say I have ever seen one of a Solent 4. However we do have a real example still in NZ so guess we are in the best place to find out!
David D

[Dave Homewood]

Does this help:

[Dave Homewood]

I have blown that up as best I can

[kiwithrottlejockey]

Jul 17, 2017 17:11:58 GMT 12 davidd said:

After reading up all the information I have to hand on Sunderlands, Solents, etc, I can find no evidence that TEAL's four Mk. 4s ever had their engines mounted at a different angle to those mounted in all the other Solents, and earlier Sunderlands; even the giant Shetland looks as though it also mounted canted-out engines. It is perfectly true that George Bolt severely criticised the installation of the P&W Twin Wasps in TEAL's Sandringhams, but these were soon modified in Australia by QANTAS, and further work was carried out on them later by TEAL to convert them to allegedly quite reliable units. Apparently the BOAC Sandringhams gave fairly reliable service, and TEAL also operated its four aircraft for some four years without too much further trouble. Interestingly the RNZAF's Sunderland 5s operated quite successfully for many years with identical engines and similar props, although it is possible that there were subtle differences in the engine cowlings. It is also intriguing that TEAL insisted that the conditions encountered on regular summer services flown by the Sandringhams over the Tasman Sea should be regarded as equivalent to operating in a tropical climate, and reckoned that the certification of the Sandringhams had all been conducted during the northern winter. It is probably pertinent to point out that RNZAF Sunderlands would be flown on most occasions at weights considerably less than would be normal on the commercial Sandringhams over the Tasman, which typically took off at near maximum gross weight of 60,000 pounds. Nevertheless, there was still something not quite right with the Twin Wasp installation on the Sandringhams, and it is possible that the mods developed for these aircraft by QANTAS and TEAL ended up being incorporated in the later RNZAF aircraft. Can anybody provide a plan photograph of a Solent 4 clearly showing the engine angles as incontrovertible proof of the non-splayed engines on this model? Is it just a myth, or have I missed something? It must be easy enough to detect this by simply looking at the example at MoTaT. The story has been repeated for many years, but is it true? The very detailed Putnam's book on the aircraft of Shorts (by C H Barnes) makes no mention of this in the section on the TEAL boats, and it would have been quite a major engineering change from all previous Solents.
The reason usually given for the splayed-out mounting of engines on the later Short flying boats (from Sunderland onwards) was simply that this was due to increasing the sweep back of the wings, due to CoG considerations, which is perfectly true. However it is also quite likely that this type of configuration would also assist in flying these aircraft should one of the engines fail, at the expense of a small speed penalty speed due to the angled-out engines. The Shorts monoplane flying boats as well as the Junkers 52/3m were the best know examples of this type of engine configuration.
David D

Just taking a quick look at two books I have (there are several more in various bookcases), first up, Air Britain's book “Ocean Sentinel — The Short Sunderland” by John F Hamlin; the section on the Solent 4 specifically states that on the Mk.4 Solents, the 2,040hp Bristol Hercules 733 engines were aligned parallel to the fuselage, unlike the earlier Solents and Seafords.

In “Flying Boats and Amphibians since 1945” by David Oliver, published by Airlife Publishing in 1987 (I've got a copy of the 1996 reprint); in the chapter on the Short S.45A Solent, there is a whole heap of information. I quote the following excert from pages 32, 33 and 34....


At the end of the year (1954) Aquila purchased two of TEAL's recently retired Solent 4s, Aotearoa II and Awatere, which were re-registered G-AOBL and G-ANYI respectively.

Captain Doug Pearson, Aquila's Chief Pilot flew all marks of the Solent and remembers it with affection.

“A most beautiful flying boat, very light on the controls. So light in fact that they were counter-balanced to introduce some feel into them. It had a larger turning circle on the water than either the Snderland or Sandringham due to its physical size but this presented no real problems to the experienced Solent pilot.

“Her only real problem was a cross-wind take-off (as with most large flying boats). Each pilot developed his own technique for this manoeuvre and I seem to have favoured running along the swell, trying to ignore the wind if possible. The cross-wind take-off, of course, depended on the length of the swell, wind direction and restrictions on take-off direction, if any. As you will appreciate, power was brought up on the out-of-wind engines, leading with the outer to counteract swing and to keep the take-off run as straight as possible; at the same time trying to counteract the “weathercocking” effect inherent in all large flying boats. Also, the wind had to be kept from lifting the into-wind wing and consequently dragging the opposite float in the water. Engine torque effect could also play a part, either aiding or hindering the take-off depending on the wind direction.

“The Marks 2 and 3 were basically the same to handle while flying. BOAC, however, had problems with the hydrodynamic qualities of the Mk.2. It seems the wingtip float clearance was insufficient at its 78,000lb [35,380kg] take-off weight. The Solent 2s were taken out of service for a short period in 1948 and their floats were repositioned eighteen inches [45cm] foward and 87 inches (2.2m) outboard; they were also more robustly mounted on two pairs of inclined struts, eliminating the need for spanwise wire bracing. This modification was incorporated into the Marks 3 and 4 during construction.

“I believe BOAC also had problems with vibration through the airframe in the early days. This was eventually traced to the engines which still had the Sunderland characteristic of pointing slightly outwards and upwards from the line of flight. Apparently the propellor manufacturers (de Havilland) did not realis this and the props on early Solents only had a very short life, about sixty hours I believe. The engines themselves also undersent some modification. BOAC used the Hercules 637, 1,690hp, fourteen-cylinder radial. By the time I flew them in service with Aquila (although I did fly one BOAC boat, G-AHIO, to get the type on my licence), the Solent 2s and 3s they used were fitted with the Hercules 637V. I believe that this was something to do with the master rods which were now opposed on a V rather than diagonally. This again was to cut down the vibration.

“The Mark 4 Solent was a completely different flying boat. TEAL had laid down some very stringent specifications. The more powerful 2,040hp Hercules 733s were fitted so that they pointed in line of flight. This put all the power where it was required and cut down on the built-in drag the engines of the 2 and 3 created. These Solents were fast and smooth and had a greater range than the earlier marks. I recall being on a tropping charter out of Cyprus with one of the 4s, while a colleague was using a Mk.3, and I overhauled the Mk.3 in flight and beat her back to Southampton by quite a margin. The avionics fit, to use a modern term, was also much better in the Mk 4, one of the items I recall having fitted as standard was an electronic auto-pilot.”


I also seem to recall that in his book “A Noble Chance”, Captain Maurice McGreal also wrote about the engine installation in the Solent 4s and how the engines were aligned into the line of flight instead of being splayed slightly outwards as with the earlier Solents, as well as the Sunderlands and Sandringhams.

[harrysone]

ARAPARIMA was the lame duck of Teal's fleet it was a mk3 and considered underpowered

[johnnyfalcon]

Those photos prove the point - did you take that snap Dave?

[Dave Homewood]

Google Earth.

[harrysone]

the 'flooded kitchen floor' look

solent_1 by Harry Follas, on Flickr

[davidd]

Dave H and Kiwithrottlejockey,
That overhead photo certainly makes the point that the Solent 4 was indeed a very different beasty, and definitely has the engine centre lines parallel with the a/c's c/l. Having the Sunderland in the same shot is an unexpected bonus, as it clearly shows the outward splay of its engines very clearly, even though the "splay" angle was only a very few degrees. So my faith in C H Barnes and the Putnam book now seems rather misplaced, although he does have an amazing amount of anecdotes and apparent knowledge on the solving of technical problems on many of the big boats, and particularly with respect to the Empires, Sunderlands and Sandringhams, and the Solents. I was also hoping that Geoffrey Wells, in his book "Head in the Clouds" (1973) would comment on this feature, but he didn't, despite his name appearing in another reference as being one of the team (under G B Bolt) who helped cure the "ills" on the Sandringhams, and therefore (I felt) would have had an interest in this problem. I should have also looked up "Jane's AWA" for 1949 or 1950, as these generally have a certain amount of technical information on new types and versions of aircraft, although not to be compared with having the actual maintenance manuals for the type. Also very obvious in the overhead view is that the Solent has a very similar wing planform to the Short Stirling, although of course the Stirling wing was of considerably lesser span than the flying boats, even allowing for the fact that the Stirling had a very narrow fuselage as compared to the beamy flying boats. (And please, NO discussion on why the Stirling span was just 99 feet!)
The angling-out of some wing-mounted engines, with a known slight detrimental effect on overall performance leads me to raise another subject in aircraft design, and that is the "washout" built into the mainplanes of just about all aircraft since the (1920s? Or did it start in WW1?) which must have lead to a slight decrease in some performance parameters. This washout had the effect of lessening the angle of attack towards the tips, thus inducing a stall near the root end before the outer wing could do likewise. The washout is a design trade off, in the interests of hoped-for safety at the expense of slightly increased drag of the outer wing sections. Wing washout is frequently overlooked when people study a new type of aircraft for the first time, unless they are looking for it. It is particularly obvious on the Japanese Zero-sen fighter (1939 design) as, from low frontal angles, it appears to have an almost elliptical wing shape, and this must have been an accepted handicap to maximum speed, as well as a small reduction in cruising range, although in service this was accepted and not really commented on. The Harvard/AT-6 is another aircraft with quite prominent washout, but again this is an accepted part of its performance.
David D

[Mustang51]

Wirraway has no or imperceptible washout so very tricky low and slow. That's the major difference between the later Harvards and Wirraway. Guessing that the Harvard I was same as Wirraway.

[harrysone]

Its also interesting to note the increased horizontal stab span on the Solent, versus the Sunderland. That's something I changed when I refurbished the kit. I used the tips of an old Airfix zero's wings for this

[johnnyfalcon]

Jul 18, 2017 11:04:18 GMT 12 harrysone said:

...I used the tips of an old Airfix zero's wings for this

Did you keep the 'washout'? (ducking for cover)