Sopwith Pups

[EricGoedkoop]

I've very often seen the Pup described as "delightful" to fly. A high compliment, no doubt - but "delightful" doesn't win dogfights.

I suspect that the Pup was abandoned in favor of the Camel rather than upgraded because ultimately more power wouldn't have given the girl any teeth. The qualities that make an aeroplane a better than average dogfighter also usually make a rotary-powered aeroplane dangerous. The differences in design between the Pup and the Camel illustrate this. The Pup was an excellent all-around design for rotary power, and that very fact limited its potency as a war machine but also gave it a second career afterward as the Dove.

[Brad]

Taz
Makes you wonder why the Pup was never up-engined

Originally Posted by EricGoedkoop

Was it ever tried?

Ummm... maybe not then, but Culp is doing a replica with a big modern radial and gobs of power. It's supposed to be a big, fast, aerobatic ship, with relatively docile handling.

I don't know how "accurate" it is- I know they use a steel tube fuselage instead of wood, but otherwise I think it looks pretty authentic.

Brad

[TomVrille]

The Sopwith Pup by Bruce, Page, and Sturtivant devotes a chapter to Pup engine options. The highlights of this chapter (again in my opinion) are that the standard Pup engine was the 80hp Le Rhône 9C, but a number of Pups were also equipped with the 80hp Clerget 7C. Availability appears to have been the major factor for this variation. Most of the Clerget Pups that entered active service ended up in the Middle Eastern theater, while the Le Rhône Pups were far and away the dominant model in France.
Attempts to upgrade performance included testing of variants with the 100hp Gnome Monosaupape and the 110hp Le Rhône 9J. Initial trials in April of 1917 showed that the Gnome Pup was 0.5mph slower than the standard Pup at 10,000 ft, but that the rate of climb was improved. Subsequent trials with a modified cowling showed an increase of 2.5mph at 10,000 ft, and further improvement in climb rate. A negative reception by Generals Brooke-Popham and Trenchard appears to have been a factor in deciding against use of the Gnome Pups at the front. Further performance improvements were noted in trials with the Le Rhône 9J, beginning in September, 1917. Structural concerns were raised to stall any consideration of a modification to this configuration.

Note that by the time of the improved performance trials, systems such as the S.E.5a and the Camel were coming on-line. In today's world, there is a great reluctance to threaten the production start of any new system with the promise of a cheaper modification program with dated equipment. One suspects that much the same attitude was present in 1917.

[Taz]

Tom- Good stuff. You are right. With the Camel in the pipeline, why fool around with a 2 year old design?

F=MA- Only knew the Tripehound had wing failures, not that they were only from ones built by subcontractors. Where is a good place to read up on those failures?

Terry Phillips
Taz

[JG1Schorner]

I have to pick a small nit about the BE2c in that it was not obsolete when introduced. The BE2 (not necessarily c) was a superb aircraft when it was introduced ... in 1913 .

Good bit on it in Sopwith Triplane Aces of the World War One, Norman Franks, as well as Collishaw's somewhat colourful biography, Air Command, as I recall.

The Sopwith Tripe was reputedly the best diving plane in the Allied inventory at the time. It was referred to as a "meteor" in dive, able to overhaul anything. The Shuttleworth versions could do it too but, they tended to come apart at the end, which probably wasn't fun.

F=MA

[Taz]

F=MA- Have the Osprey book, but have only glanced through it. Will read more carefully now. Will try and find a copy of Collishaw's book as well. Still remember the photos of a Tripe in The Fighting Triplanes pulling 6 gs for a few seconds. Assume the test was done with a Sopwith-built aircraft. It sure scared the Germans when it showed up. Their diving in the Albatros D.III-Va series was limited due to fear of the single spar lower wing.

Terry Phillips
Taz

[Lufbery]

Originally Posted by jtisch

I am not a Pup expert (or expert on anything for that matter) but I seem to remember reading somewhere that it performed well at high altitude, which seems odd as it had a rotary engine but on the other hand it also had a rather light wing loading. I'll rummage around my shop/library to see if I can find that reference.

Yes, Arthur Gould Lee makes that observation in his book, No Parachute. It's an excellent read.

Regards,

Originally Posted by Lufbery

Yes, Arthur Gould Lee makes that observation in his book, No Parachute. It's an excellent read.

Regards,

Yes, he mentions above 15,000ft, the Pup would outmaneauver Albatroses. And yes it is a fantastic read! Funny story... I've owned the book three times (always paperback). I read it in the 70's. Did a major housecleaning in the 80s. Felt bad about getting rid of it in the 90's and reacquired it to re-read. It disappeared prior to re-reading. Earlier this year, I wanted to read it again and watched prices around the net... none less than $60.00 for hardback. Watched some more, watched some more... finally! Found a paperback version for $14.00 thru Amazon. After a $5.00 shipping charge I received the book for $19.00. I saved $40.00+! I was happy. While re-reading it, I just happened to find it on Ebay for $3.00. *sigh* (ROFL!)

[Taz]

--E- Would not worry. I never felt like I ever wasted any money buying a book. Maybe did not get the best price on some, but it all evens out in the end.

Terry Phillips
Taz