even on 1.80 ata the K-4 has a better power to weight ratio to the mkXIV,and yet it slower and don't climb as well,if you think about it,for that P/W ratio,it's performance is pretty poor.
could this be down to it 3-blade prop?
Maximum speeds must always be specified with the altitude at which they occur. The Sptifire XIV had a two stage intercooled supercharger that lost less power at high altitude (about 25000ft) and was thus able to fly faster at that altitude because there air presents less drag.
Of all the single stage supercharged engines the DB605DB and DC had the best altitude performance since the Daimler Benz's engine used a high compression ratio rather than a high boost ratio to obtain power and efficiency leaving the supercharger disposed to provide altitude compensation rather than boost.
At sea level a Me 109K4 on C3 fuel with MW50 was faster than the Spitfire XIV on PN150 fuel both at 1.8 and 1.98ata. About 16mph for the latter. Some of the post war boost ratings of the Griffon might have eliminated this gap.
The Me 109K4 in good condition with retractable tail wheel and with the undercarriage wheel doors fitted might manage 444mph on 1.98ata and also at 1.8ata, the difference being that at 1.98ata the speed was higher below the superchargers full pressure altitude.
Propellers can be optimised to produce their best 'thrust' at either low, medium or high speeds. By fitting a 'thin' propeller optimised for high speed the Me 109K4 could achieve around 454 mph at a slight cost in climb rate. A more advanced scimitar propeller was expected to achieve 460mph or more.
When the notification for rescinding of the 1.98 ata rating went out it noted that Me 109K4 reconnaissance units already being used at 1.98ata could be run to 1.9ata until they failed but must then be run at 1.8 ata. No problems were noted in engine overheating or seizure. The problems were related to knocking and pre-ignition and make note of the need to retard the ignition (a classic measure to prevent knocking). This means that had the Germans had a supply of a better fuel (105/135 say) they probably could have run those engines at 1.98ata. Alternatively a cooler running spark plug.
The Me 109K14 had the DB605L engine, essentially at two stage supercharger version without intercooler. With this engine running at 1.75 ata and a new 4 blade prop to gain purchase in thin air the aircraft had a speed of about 454mph at 31000ft. This is not down on the Spitfire Mk XIV but this did not enter service.
The Spitfire XIV still had the old wing developed for the Mk VIII wing and so aero elastic twist at high speed reduced its roll rate response. The new stiffer wing with balance tabs only came in on the Mk22. The Me 109K4 did not have as significant an aeroeleastic twist problem but had stiff ailerons at high speed due to compressibility, it could still be rolled. The solution was to be spring tabs or 'flettner' tabs to reduce force. Late war US navy fighters used these, so did several axis aircraft. I have my doubts about them and believe hydraulics was the only way to go.
If you were involved at a sea level fight a Me 109K4 was a bit faster. The Tempest V was the RAF's low altitude specialist.
The Luftwaffe was in the process of replacing the Me 109K,Fw 190A with jets and the Focke-Wulf 190D series and the Ta 152B,C and H.
Hence the question is a little displaced. The Me 109 belongs in the Hurricane era, perhaps the question should be 'what is better a Griffon or Merlin 66 powered Hurricane or a Me 109K4.
In some scenarios this might have happened.
