sopwith camel kill/loss ratio

"Russell Waterson" writes:

"Stephen Harker" wrote in message
...
Stephen Harding writes:

Russell Waterson wrote:

There is a book called "Winged Victory" first pubished in 1934 by a
Camel
pilot by V. M. Yeates tells about flying them in battle in 1918. The
camel
was not fast and could not catch anything in a tail chase. The Germans
found
that hit and run tactics were the only way to take them on and have
any
success. They were fine against Dr1 because they were in the same
boat, slow
but manouverable. the camels were used more at mid to low altitude
while
SE5a and Dolphines went performed better higher. [...]

I always thought the Sopwith Camel was pretty fast; 130 mph or so, as
well as
maneuverable. It's generally considered the best Allied fighter of WWI
(I think), although Spad and SE5a have their adherents.

I'll try to look up some numbers tonight (JM Bruce _War Planes of the
First World War_ or the Profile series may cover this), but my memory
of various references matches the comments from "Winged Victory". The
numbers I have in memory for Camels are around 120 mph at sea level,
the SE5a was around 130 to 135 mph at sea level. The Camel
performance was supposed to fall off more rapidly with height. [...]
It is probably true that variations in engine output and
reliability was greater in WW1 than in WW2 due to lower metallurgical
and other quality control, which would further complicate matters.

It needs to be remembered that when the performance figures are
expressed say at max 130 mph that usually means when the aircraft is
new and running well. Most aircraft especially in ww1 would not be
able to go the max speed as they got damaged, worn out, maintainance
not up to scatch etc. It might be said that the Camel went 120 but
in reality it was more like 110 or even less.

That is a given in any aircraft comparison. The recorded comments of
the US naval aviators in late 1944 about the reduced performance of
the old Hellcats being a case in point. Unfortunately most published
figures don't record details of engine and aircraft use for WW1, the
prototype figures being an obvious exception. The original data may
have this, but most of the sources I have looked at don't. That said,
these are some figures for Camels and some comparison aircraft. Some
of these number were clearly `calculator converted' from metric.
There may be enough aircraft to get some idea of trends, but more data
would help.

Max Speed at height Serv Ceil Climb Climb Engine Ref
(mph) (feet) (feet) 10,000 15,000
(m:s) (m:s)

Camel F1 115 6,500 19,000 130hp Clerget [1]
Camel F1 122 SL 24,000 110hp Le Rhone[1]
Camel F1 117 10,000 21,000 150hp BR1 [1]
Camel F1 110 10,000 18,500 100hp Monosoupape[1]
Camel F1 104.5 10,000 18,000 11:45 23:15 130hp Clerget [2]

Some comparison data:

Dolphin 1 121 10,000 20,000 200hp H-S [1]
Dolphin 1 127 10,000 21,000 10:30 19:30 200hp H-S [5]
SE5a 135 SL NA 240hp H-S [1]
SE5a 137 SL NA 200hp Viper [1]
SE5a 126 10,000 17,000 13:15 27:35 200hp H-S [2]
SE5a 120 15,000 19,500 10:50 20:50 200hp Viper [3]
Fokker DVII 117 3,280 19,685 Mercedes [1]
Albatros DV 116 3,280 20,500 Mercedes [1]
Albatros DV 103 NA NA Mercedes [4]
Spad XIII 139 6,500 21,800 220hp H-S [1]

[1] J W R Taylor, Combat Aircraft of the World, Ebury Press and
Michael Joseph, London 1969
[2] J M Bruce, War Planes of the First World War, Fighters Vol 2,
MacDonald, London 1968
[3] The SE5a, Profile 1, Profile Publications, 1971
[4] The Albatros DV, Profile 9, Profile Publications, 1965
[5] The Sopwith Dolphin, Profile 169, Profile Publications, 1967

There is clearly a fairly large variation in performance even with
nominally the same engine. This is not too surprising: in late 1917
who Wolseley had the British licence to manufacture the Hispano-Suiza
had major problems and a lot of their engines were defective, one of
the French suppliers produced engines with defective gears. The
prototype SE5a with a French 200hp Hispano-Suiza recorded considerably
better climbing performance and service ceiling than the one listed
above. This may reflect the engine age/wear or quality control
problems.

In 1918 did not have the testing regime and materials knowledge to
rapidly improve this. A large number of British 1918 designs were
supposed to use the ABC Dragonfly radial ordered off the drawing
board. The Dragonfly proved incurably defective and the designs using
it got nowhere. A couple did appear in modified form later using the
Bristol Jupiter (ex Cosmos Jupiter) the first engine to pass a type
test (20 Hour?) which was introduced following this debacle. Bristols
put a lot of work into design and materials selection to improve
reliability and ease maintenance, this takes time that was not
available in the war.

--
Stephen Harker
School of Physics & Materials Engineering
Monash University http://www.ph.adfa.edu.au/s-harker/
Baloney Baffles brains: Eric Frank Russell

That is facinating. You did put some work into this and I appreciate it. It
is very interesting especially when we are trying to get a handle on what it
was like for them. I am not sure but it is a guess any way, but would a
squadron have an aircraft like the camel and have them with different
engines and hence different performances? E.g. one pilot have the Clerget
another the Bentley another the Br1 etc.

It would make maintainance difficult and formation flying hard. The
idiosyncrasies of of each type would be different so to go from one aircraft
to another would test the skill of a pilot when they had to swap an
aircraft. Does anyone kow much about that?

"Stephen Harker" wrote in message
...
"Russell Waterson" writes:

"Stephen Harker" wrote in message
...
Stephen Harding writes:

Russell Waterson wrote:

There is a book called "Winged Victory" first pubished in 1934 by
a
Camel
pilot by V. M. Yeates tells about flying them in battle in 1918.
The
camel
was not fast and could not catch anything in a tail chase. The
Germans
found
that hit and run tactics were the only way to take them on and
have
any
success. They were fine against Dr1 because they were in the same
boat, slow
but manouverable. the camels were used more at mid to low altitude
while
SE5a and Dolphines went performed better higher. [...]

I always thought the Sopwith Camel was pretty fast; 130 mph or so,
as
well as
maneuverable. It's generally considered the best Allied fighter of
WWI
(I think), although Spad and SE5a have their adherents.

I'll try to look up some numbers tonight (JM Bruce _War Planes of the
First World War_ or the Profile series may cover this), but my memory
of various references matches the comments from "Winged Victory". The
numbers I have in memory for Camels are around 120 mph at sea level,
the SE5a was around 130 to 135 mph at sea level. The Camel
performance was supposed to fall off more rapidly with height. [...]
It is probably true that variations in engine output and
reliability was greater in WW1 than in WW2 due to lower metallurgical
and other quality control, which would further complicate matters.

It needs to be remembered that when the performance figures are
expressed say at max 130 mph that usually means when the aircraft is
new and running well. Most aircraft especially in ww1 would not be
able to go the max speed as they got damaged, worn out, maintainance
not up to scatch etc. It might be said that the Camel went 120 but
in reality it was more like 110 or even less.

That is a given in any aircraft comparison. The recorded comments of
the US naval aviators in late 1944 about the reduced performance of
the old Hellcats being a case in point. Unfortunately most published
figures don't record details of engine and aircraft use for WW1, the
prototype figures being an obvious exception. The original data may
have this, but most of the sources I have looked at don't. That said,
these are some figures for Camels and some comparison aircraft. Some
of these number were clearly `calculator converted' from metric.
There may be enough aircraft to get some idea of trends, but more data
would help.

Max Speed at height Serv Ceil Climb Climb Engine Ref
(mph) (feet) (feet) 10,000 15,000
(m:s) (m:s)

Camel F1 115 6,500 19,000 130hp Clerget [1]
Camel F1 122 SL 24,000 110hp Le Rhone[1]
Camel F1 117 10,000 21,000 150hp BR1 [1]
Camel F1 110 10,000 18,500 100hp
Monosoupape[1]
Camel F1 104.5 10,000 18,000 11:45 23:15 130hp Clerget [2]

Some comparison data:

Dolphin 1 121 10,000 20,000 200hp H-S [1]
Dolphin 1 127 10,000 21,000 10:30 19:30 200hp H-S [5]
SE5a 135 SL NA 240hp H-S [1]
SE5a 137 SL NA 200hp Viper [1]
SE5a 126 10,000 17,000 13:15 27:35 200hp H-S [2]
SE5a 120 15,000 19,500 10:50 20:50 200hp Viper [3]
Fokker DVII 117 3,280 19,685 Mercedes [1]
Albatros DV 116 3,280 20,500 Mercedes [1]
Albatros DV 103 NA NA Mercedes [4]
Spad XIII 139 6,500 21,800 220hp H-S [1]

[1] J W R Taylor, Combat Aircraft of the World, Ebury Press and
Michael Joseph, London 1969
[2] J M Bruce, War Planes of the First World War, Fighters Vol 2,
MacDonald, London 1968
[3] The SE5a, Profile 1, Profile Publications, 1971
[4] The Albatros DV, Profile 9, Profile Publications, 1965
[5] The Sopwith Dolphin, Profile 169, Profile Publications, 1967

There is clearly a fairly large variation in performance even with
nominally the same engine. This is not too surprising: in late 1917
who Wolseley had the British licence to manufacture the Hispano-Suiza
had major problems and a lot of their engines were defective, one of
the French suppliers produced engines with defective gears. The
prototype SE5a with a French 200hp Hispano-Suiza recorded considerably
better climbing performance and service ceiling than the one listed
above. This may reflect the engine age/wear or quality control
problems.

In 1918 did not have the testing regime and materials knowledge to
rapidly improve this. A large number of British 1918 designs were
supposed to use the ABC Dragonfly radial ordered off the drawing
board. The Dragonfly proved incurably defective and the designs using
it got nowhere. A couple did appear in modified form later using the
Bristol Jupiter (ex Cosmos Jupiter) the first engine to pass a type
test (20 Hour?) which was introduced following this debacle. Bristols
put a lot of work into design and materials selection to improve
reliability and ease maintenance, this takes time that was not
available in the war.

--
Stephen Harker
School of Physics & Materials Engineering
Monash University
http://www.ph.adfa.edu.au/s-harker/
Baloney Baffles brains: Eric Frank
Russell

"Russell Waterson" writes:

That is facinating. You did put some work into this and I appreciate it. It
is very interesting especially when we are trying to get a handle on what it
was like for them. I am not sure but it is a guess any way, but would a
squadron have an aircraft like the camel and have them with different
engines and hence different performances? E.g. one pilot have the Clerget
another the Bentley another the Br1 etc.

That is a good question. Looking through the references I don't see
an answer. According to the records the RNAS ordered mainly Clerget
and BR1 engined Camels. The RFC may have mainly ordered Clerget
engined Camels (this is my inference from the wording and not
reliable). This would suggest that it is possible that they had mixed
engines in the one squadron and indeed flight. If this was the case
there would have been a considerable advantage in the aircraft with
better performance as these numbers suggest a 10% advantage in speed
was possible.

As a pointer in _Five Years in the Royal Flying Corps_ James McCudden
describes how he installed an engine with the high compression pistons
in his SE5a (taking it from 200hp to 220hp or 240hp). Together with
taking great care with his engine he was able to regularly achieve
22,000 ft and was able to catch and shoot down the high flying Rumpler
reconnaisance aircraft. McCudden at least once mentioned that when he
had to use someone elses aircraft the lower performance was obvious.
McCudden was a mechanic by background and this probably helped in
making sure that the engines were kept to the highest standard.

It would make maintainance difficult and formation flying hard. The
idiosyncrasies of of each type would be different so to go from one aircraft
to another would test the skill of a pilot when they had to swap an
aircraft. Does anyone kow much about that?

It would be interesting to have some real information on this. I
would expect that, to a large extent, when flying in formation the
pilots could compensate by the throttle setting, after all when on
patrol they would be flying at considerably less than the maximum
speed and hence it was less of a problem. The maintenance question
could be quite a significant one. However, remember that a lot of
changes in the first world war were ad hoc. Up to 1916 or thereabouts
most squadrons had multiple types of aircraft. The move to
standardisation was probably impeded by the manufacturing limitations.
They may have _preferred_ to have aircraft with the same engine in the
squadron, but had to take what was available. The expansion of the
service may have made it hard to achieve standardisation. Looking at
the references suggests (my inference again) that there was a tendency
to reduce the number of engine types actually used in a given
aircraft. A lot of engines were tested but not actually used in
service. Some hard evidence would be useful.

--
Stephen Harker
School of Physics & Materials Engineering
Monash University http://www.ph.adfa.edu.au/s-harker/
Baloney Baffles brains: Eric Frank Russell

Stephen Harker wrote:

It would be interesting to have some real information on this. I
would expect that, to a large extent, when flying in formation the
pilots could compensate by the throttle setting, after all when on
patrol they would be flying at considerably less than the maximum
speed and hence it was less of a problem.

I haven't been following this thread too closely but if it hasn't been
mentioned yet, remember that those old WW1 rotary engines didn't
have throttles. The pilot used an "interupter" switch to alternately
kill the ignition and restart it so as to adjust their speeds. A good
example of this technique (called "blipping") being used is in the
1975 movie, "The Great Waldo Pepper" starring Robert Redford.

Mike Marron wrote:

Stephen Harker wrote:

It would be interesting to have some real information on this. I
would expect that, to a large extent, when flying in formation the
pilots could compensate by the throttle setting, after all when on
patrol they would be flying at considerably less than the maximum
speed and hence it was less of a problem.

I haven't been following this thread too closely but if it hasn't been
mentioned yet, remember that those old WW1 rotary engines didn't
have throttles. The pilot used an "interupter" switch to alternately
kill the ignition and restart it so as to adjust their speeds. A good
example of this technique (called "blipping") being used is in the
1975 movie, "The Great Waldo Pepper" starring Robert Redford.

I don't believe "blipping" was a characteristic of all rotary engines
though was it? Certainly was in the case of the Camel.

I've heard and seen the Camel in flight (genuine engine; reproduction
aircraft) at Rhinebeck airfield (see http://hobart.cs.umass.edu/~harding/Rhinebeck/
for some pics I took during a visit in 2001, including the Sopwith Camel)
and it really is quite distinctive sounding in flight.

I would think staying together would be quite challenging given different
engines, different age/wear of the engines, and the blipping throttle
control requirement.

Even during WWII, I've read accounts of the same model aircraft having
difficulties staying together because of differences in engine wear.


SMH

Stephen Harding wrote:
Mike Marron wrote:
Stephen Harker wrote:

It would be interesting to have some real information on this. I
would expect that, to a large extent, when flying in formation the
pilots could compensate by the throttle setting, after all when on
patrol they would be flying at considerably less than the maximum
speed and hence it was less of a problem.

I haven't been following this thread too closely but if it hasn't been
mentioned yet, remember that those old WW1 rotary engines didn't
have throttles. The pilot used an "interupter" switch to alternately
kill the ignition and restart it so as to adjust their speeds. A good
example of this technique (called "blipping") being used is in the
1975 movie, "The Great Waldo Pepper" starring Robert Redford.

I don't believe "blipping" was a characteristic of all rotary engines
though was it? Certainly was in the case of the Camel.

Probably not "all" but AFAIK blipping was a characteristic of the
vast majority of WW1 rotarys.

I've heard and seen the Camel in flight (genuine engine; reproduction
aircraft) at Rhinebeck airfield (see http://hobart.cs.umass.edu/~harding/Rhinebeck/
for some pics I took during a visit in 2001, including the Sopwith Camel)
and it really is quite distinctive sounding in flight.

Yep. I understand that severe backfires as the result of blipping
sometimes caused fires to erupt inflight which of course would
promptly engulf the entire dope 'n fabric airframes.

I would think staying together would be quite challenging given different
engines, different age/wear of the engines, and the blipping throttle
control requirement.

All true, not to mention the lack of 2-way radio communications.

Even during WWII, I've read accounts of the same model aircraft having
difficulties staying together because of differences in engine wear.

As an aside, besides complete engine failures I've also experienced
a runaway engine at WOT (wide open throttle) while flying in formation
with a bud. My throttle cable broke while flying crosscountry at our
normal cruising altitude of 5-10 ft. AGL underneath the powerlines and
bridges while hopscotching over the hedgerows and terrorizing any
cow, deer, or other four-legged critter who happens to get in our way.

My options were either to hit the mag switches and kill the runaway
engine, or simply go with the flow and let the bird do it's thing and
climb, climb, climb. I chose the latter and radioed my bud that I was
diverting to the nearest airport. By the time we reached our
alternate, we had climbed up to about 8,000 ft. AGL at which time
I simply shut down the runaway engine and glided down to an
uneventful dead stick landing.