Inverted V engine vs. V engine

[Shortround6]

Including post war over 8000 Griffons were built.

 

[Tante Ju]

And during war for normal comperison? I can think of about 1000 aircraft produce with Griffon, so, by relativ, it was not very considered "series" produce .

 

[Juha]

Hello Tante Ju
appr 1000 planes with one-stage early Griffons and appr 1200 Spitfires with 60-series 2-stage Griffons (XIV, XIX, 21 and early 22s)+other types, so IMHO at least 3000 Griffons were built during WWII.

Juha

 

[wuzak]

Spitfire XIV first flew in early 1943, with Griffon 61 IIRC, and production machines were rolling off the line in October 1943 with the Griffon 65.

 

[Tante Ju]

I saw numbers by bada show 300 XIVs produce until 1945. Plus 100 XII perhaps.. thats 400 planes, until 1945, but probably more Griffon, perhaps twice given Griffon had low lifespan. Plus about 800 Fairey Fireflys. Most seem post war.

So production was rather low. Perhaps RR was occupied with Merlin, or Griffon was that more costly?

 

[Milosh]

I count 734 Spirfire Mk XIVs built til June 1945 in Spitfire: The History.

Tell us more about this low TBO of the Griffon please.

 

[Tante Ju]

Hi!

Yes most wartime produce was 1945.

Griffon 65 series required change to new engine after about 40 hour operation.

 

[otftch]

I've just read this entire thread and have only one thing to add that will not cause an argument; Both are superior to a twisted rubber band !
Ed

 

[Shortround6]

Many more Griffons were produced.

I am not sure where the end of WW II production cut off comes from in the evaluation an engine design. I do understand that an engine in production and service is a different category than one that existed only on paper or even on test stands though.

I did give some numbers from a post war Jumo 213, I think they are interesting because it was model of the engine that was produced to use standard 100/130 fuel , wither that is good or bad I am not going to guess but it does give a common point of reference rather than guessing or speculating about what the German C-4 fuel was like compared to allied fuel at a given point in 1943-45. Being produced in 1949-55 it also should eliminate any squawks about shortages of certain alloys for critical parts. It was used to power a French Nord flying boat of which over 20 were built so the number of engines should have been around 50-60 including a normal number of spares. Not a big number but certainly better than using a test stand engine or one or two flying experimental engines. The engine may have been down rated in the interests of longevity and didn't have a WEP rating but it was rated at for take-off 2,300hp at 3250rpm using 11lbs boost (1.74Ata?) using water injection and 2100hp same conditions dry. Normal rating (climb or 1/2 hour or 1 hour or ?) was 1720hp at 3000rpm at 1800meters boost not given and 1500hp at 3000rpm and 5000meters in high gear. Cruise rating was 1060hp at 2400rpm at 2800 meters and 1000hp at 2400hp at 5200meters.
I do not have any figures for engine life.

 

[spicmart]

I don't see this clear advantage!

DB 603N 1944/45; C3 fuel; two stage supercharger, dry weight 950kg; 2800PS!

Jumo 213J 1944/45, B4 fuel, two stage supercharger, dry weight 920kg; 2240PS!

IIRC the Jumo 213J with 4 valves technology was to be rated at about 2700PS according to Dietmar Herrmanns Ta 152 Book.

 

[Mustang nut]

The Griffon was only fitted to the Spitfire and Firefly during the war there were rarely more than 1000 spitfires in front line service, by 1945 the war was almost over and jets were the way forward. De Havilland did consider Griffons and Sabres for the Mosquito as future possibilities but stuck with the Merlin.

I've just read this entire thread and have only one thing to add that will not cause an argument; Both are superior to a twisted rubber band ! Ed

I had a balsa spitfire powered by the famous rolls royce subbuteo rubber band, it was much superior to my the Bf 109 of friend Heinrich Hasenfuss in climb and top speed, he always wound it up with the plane inverted.

 

[Shortround6]

IIRC the Jumo 213J with 4 valves technology was to be rated at about 2700PS according to Dietmar Herrmanns Ta 152 Book.

I think the key here is the "was to be rated" part.

I can find an awful lot of engines that "were to be rated at" XXXXhp at some time in the future that never made it.
For instance the Post war Bristol Hercules was supposed to be type tested at 2500hp and the Centaurus was supposed to go to 3500hp.
Turbo compound Allison.
P&W R-4360VDT, lots of places list the engine but did it ever actually fly or make the numbers listed for it?

And more, the above are developments of exiting engines and not new engines that didn't make it.

 

[wuzak]

Here is a list of production of Spitfires powered by Griffons, from
Supermarine Spitfire (Griffon powered variants) - Wikipedia, the free encyclopedia

Mark                Built by                    Built Notes 
F Mk XII            Supermarine                   100 First Mk XII 13 October 1942 
F Mk XIV, FR Mk XIV Supermarine                   957 First Mk XIV RB142 28 October 1943 
F Mk XVIII          Supermarine                   300 First Mk XVIII June 1945 
PR Mk XIX           Supermarine                   224 First Mk XIX RM626 May 1944 
F Mk 21             Castle Bromwich               120 First Mk 21 LA187 27 January 1944 
F Mk 22             Supermarine, Castle Bromwich  287 First Mk 22 March 1945 
F Mk 24             Supermarine                    54 First Mk 24 March 1946

Note that the XIV was replaced in production by the XVIII in June 1945 - that is 957 were built during the war. The XIX continued in production until 1946.

The 21 did see some operational service during WW2 as well.

 

[wuzak]

I saw numbers by bada show 300 XIVs produce until 1945. Plus 100 XII perhaps.. thats 400 planes, until 1945, but probably more Griffon, perhaps twice given Griffon had low lifespan. Plus about 800 Fairey Fireflys. Most seem post war.

So production was rather low. Perhaps RR was occupied with Merlin, or Griffon was that more costly?

Production was definitely centred on the Merlin. There were 4 required for each Lanc, 2 for each Mossie, plus ones required for the Mustang and the various Spitfire marks still in proudction.

 

[Shortround6]

From Lumsden's Book.

Griffon II..........767 built at Derby, 1942-1945
Griffon IIB.... Number not given but mounted in at least 5 different planes.
Griffon III........101 built at Derby, 1942-1944
Griffon IV.........25 built at Derby, 1942-1943
Griffon VI........860 built at Derby, 1944-1945
Griffon VIII.......30 built at Derby, 1945-1946
Griffon XII.......410 built at Derby, 1945-1947
Griffon 26........#NA
Griffon 29........#NA
Griffon 37........45 built at Derby 1946
Griffon 56........#NA
Griffon 57........891 built at Derby 1947-1953
Griffon 57A......227 built at Derby 1953-1955
Griffon 59........217 built at Derby 1951-1953
Griffon 61........434 built at Derby, 700 built at Crewe 1942-1945
Griffon 62........#NA
Griffon 64........200 built at Crew 1945
Griffon 65........525 built at Derby, 950 built at Crewe 1943-1948
Griffon 66........260 built at Derby, 100 built at Crewe 1944-1945
Griffon 67........150 built at Crewe 1945
Griffon 69........130 built at Derby, 30 built at Crewe 1945
Griffon 71...........3 built at Derby 1943
Griffon 72...........#NA
Griffon 73...........#NA
Griffon 74.......772 built at Derby, 30 built at Glasgow 1946-1952
Griffon 83..........#NA
Griffon 85.......100 built at Derby 1944-1945
Griffon 86..........#NA
Griffon 87........74 built at Crewe 1945
Griffon 88..........#NA
Griffon 89.........25 built at Crewe 1945
Type numbers keep going up but few of them were installed in aircraft even for tests. I also skipped earlier numbers that that didn't appear to be installed in an aircraft. Some of the engines listed as #NA may have been single engines or very small numbers installed as test engines but all types listed were at least installed in an airframe. How many of the larger production numbers were installed in aircraft and how many were held as spares I don't know.

 

[wuzak]

Well, lets see. The 65 was put into the XIV and XVIII. That equates to 1257 aircraft compared with 1475 engines. The 66 went into the PRXIX (it was a 65 with a cabin blower) of which 224 were built, compared with 260 engines.

The 85 went into Spitfire Mk24 (54) and the Spiteful XIV (19) - 73 out of 100 built. Maybe some Spit 22s used the 85 as well.

 

[fastmongrel]

I find it hard to believe the Griffon needed to be replaced with a new engine after 40 hours flight. By the time it has been flight tested by the factory, then flight tested by the RAF or FAA, then delivered to the Group, then delivered to the squadron base or carrier, then flight tested by the squadron it would be time to put in a new engine. Did RR deliver Griffons in 6 packs I think someone might have missed out a 0 when typing. When even early model RR Derwent jet engines were lasting 100 hours plus flight time a 40 hour life piston engine would mean someone in the factory needed shooting.

 

[Tante Ju]

Short lifespan was not uncommon for piston engine in 1944! By then, power was very great - so was strain. 40 hours - similiar for Soviet VK 107, or German DB 605D. Or consider Jumo 004B.

May not as disadvantage as seems. Consider combat sortie - 1 hour. This means plane will fly 30-40 combat sortie before engine needs replace.. but will plane be not even hit once this time? Or shot down? For wartime, it is ok. For peace - not OK.

 

[Shortround6]

They might have dropped a "2" of the front, Merlins were supposed to be good for 300hours by the end of the war.

Or it could be possible that a few (or one?) engines had to be pulled after 40 hours, perhaps at forward certain forward airfields?

If it is the forward air fields then the short time is an indication of operating conditions (many engines suffered drastically shortened lives under certain front line conditions) rather than a good indicator of design problems.

 

[fastmongrel]

May not as disadvantage as seems. Consider combat sortie - 1 hour. This means plane will fly 30-40 combat sortie before engine needs replace.. but will plane be not even hit once this time? Or shot down? For wartime, it is ok. For peace - not OK.

I dont think a Fairy Firefly would be flying 1 hour sorties. Anyway a plane doesnt get delivered to a squadron with 0 hours on the clock it will have had considerable flight testing before it gets into combat.