Spitfire V vs Spitfire V LF

[thewritingwriter89]

Anyone who plays Il2 1946 knows there is a plethora of Spit variants. Last night, my dad and I fought each other (him in his Spit Vb, and myself in a 109F-4). It was a bit lopsided battle and the 109 had a slight upperhand. So, my dad, being the low-level dogfighter that he is, demanded a better low level Spit. I didn't think they even made one but sure enough, I came across the Spit LF series. So off we went (I switched to a 109G-2 for the sake of keeping the battle contemporary). I was really suprised. The 109 still held a speed advantage, but down low there is simply no way to turn with these "LF" models. Granted, I was in a G-2 and it is a little less manuverable than a F-4, but I could definently tell, I was dealing with a different opponent. Even for a Mk Vb, that thing is like a totaly different airplane.

After doing a little research, I found that the LF was fitted with a Merlin specifically tuned for performance at 2700 ft and that the wings were clipped. However, in Il2 there is a separate Spit for the clipped wings. My dad was just flying a Spit Vb (LF), not a Spit Vb (LF CW). Understandably, the Spit Vb (LF) had better performance at low altitude but is it really possible for the LF to be that much better? Tonight I'll try the 109F-4 against the LF and try to make use of some of that manuverability. What do you guys think?

 

[kool kitty89]

I believe the difference was similarto the low level Seafires compared to the standard ones. They had cropped superchargers with WEP boost increased from +16 psi to +18 psi (and used less power) with critical altitude was much lower.

It came at a high price though as performance dropped off rapidly above ~5,000 ft. (worse than the Allison V-1710 of the P-40E/K and P-39D-1/2, though there is no usable WEP setting for these -and no P-40K- in Il-2, they only go up to Mil power)

The normal Mk.V used the Merlin 45, I the Merlin 50 was the Seafire counterpart, the cropped version was the Merlin 32 (Mk.V LF) and Merlin 50.M on the Seafire.

The Merlin 45/50 used a single-stage slingle-speed supercharger similar to the Merlin 20 series but w/out the low speed (MS) gear.

Incedentally the performance of the "cropped" version was similar to the low speed (MS) gear of the Merlin 20 (XX). So had the Spitfire been fitted with the Hurricane Mk.II's engine (proposed Spifire Mk.III) it would have had the best of both worlds. The problem there is that the 2-speed version was it was slightly longer and required modification to the engine mount. (somthing that happened with the significantly longer 2-stage models later on) The Merlin 45 could fit to the same mounting as the older Merlin II,III, and XII of the Spitfire I/II models.


There were some charts on calculated performance comparisons posted by HoHun in another thread, I think it was a Seafire/Spitfire vs Zero thread.


Though Il-2 is still just a game, probably one of the more realistic (if not the most) out there, but still known to be inaccurate in many cases. (many minor, some significant -ie lack of liquid-ccoling/radiator damage modeling) We also have an Il-2 gaming forum on here in case you didn't know. (granted your question was pertinant to the real world performance of the a/c in question)

Also I believe the Bf 109F-4 had better low alt performance than the later G-2 model. (similar engine power -w/out MW 50- down low and significantly lighter)

 

[Juha]

Especially marked was the difference in climb, Spit LF V was very good climber up to appr 3000 ft and better than normal F V up to appr 10 000ft but above that ran out of steam.

Juha

 

[antoni]

.....that the wings were clipped.

Yes and No. Clipped wings are not indicative of an LF Spitfire; especially the Mk V of which substantial numbers of standard Vbs and Vcs had their wings clipped. It was relatively easy to remove or replace the tips and could be due pilot's preference as much as anything else. It is possible to find photographs of a particular aircraft with both clipped and unclipped wings.
The answer to the introduction by the Germans of the FW 190 was a new Spitfire with the Merlin 60 series of engines (MK VIII Mk IX) or the new generation Griffon (Mk XII). In the meantime the Mk V was improved. To optimise low-altitude performance the supercharger blades of the Merlin 45, 50 55 were cropped. Giving a maximum boost of +18ib./sq.in gave a top speed of 350 mph at 5,900 ft, fairly close to that of the Fw 190. These engines were given the suffix M after the variant number. When significant role letters were introduced in February 1942 the Mk V became the F V and those equipped with M suffix engines were designated LF denoting low-altitude fighter. Most LF.Vs had their wings clipped which resulted in improved performance and manoeuvrability below 10,000 ft. It was common for the LF conversions of late 1943 and 1944 to feature late style (Mk IX) exhausts and elevators, but this was not limited to the LF.V version either. Less than a dozen Spitfires were actually built as LF.Vs. These came in the very last batches of MK Vc Trops from Westland and CBAF. All LF Vbs and virtually all LF.Vcs were conversions from regular Mk Vs, often well worn. This led to them being referred to as clipped (the wings), cropped (the supercharger) and clapped (from the English expression 'clapped out' meaning extremely tired or worn out).
The photographs.
1 2. EP509 RF*G of 303 Squadron shortly before the Normandy landings. Converted to LF standard in late 1943 when the engine was replaced with a 45M. Typically for this period the engine came with individual ejector exhausts and this photograph is sometimes erroneously captioned s a Mk IX for this reason. A late style horizontal tail was also retrofitted. At this time the squadron was equipped exclusively with LF.Vs. The Spitfire in the background has the late style exhausts confirming the replacement with an M engine but it clearly has full span wings which mean that not all LF.Vs had clipped wings.
3 4. One of Zumbach's 'Donalds' BM144 RF.D at the beginning of its service life. Later it was recoded as RF.H and repainted before finally having its wings clipped. There is no reason to suppose that this means it was converted to LF standard. Eventually it went to 315 Squadron (repainted yet again) were it was recoded PK*O still with clipped wings.

 

[Bernhart]

i believe 417 in italy used mk v that used all 3 types of wings ie clipped, regualar and the high altitude