a possible solution for overheating & low speed spitfire/hurricane in last Beta patch

[ATAG_Dutch]

Originally Posted by zapatista

suggesting in reply to a customer question about overheating, ie to close the radiator before engine start, and then never open it.

But that's the opposite of what he said Zap. He said;

'Open Cowling FULL before start engine and Do not close it!'

This would currently be equivalent to flying along with a twenty foot parachute tied to your a*se (exaggeration, just in case any purists object).

[zapatista]

Originally Posted by ATAG_Dutch

But that's the opposite of what he said Zap. He said;

'Open Cowling FULL before start engine and Do not close it!'

This would currently be equivalent to flying along with a twenty foot parachute tied to your a*se (exaggeration, just in case any purists object).

lol, errr, of course you'r right on that last one typo in that last post after a long work day (*edit made in original post)

what peaked my interest on his comment is that he set it to open before engine start, and then never touched it again, as if altering its setting after engine start might lock it closed with the engine more prone to overheating from then on (yet still be subject to drag with cowling open). whereas i, and prob most people, close it at start, then keep changing it ones the engines warms up and then mostly keep it open unless at very high altitude

at what started as a simple suggestion (from him) and my wanting to know if others had tried it, it all become a bit long winded and out of proportion, i'll try it on the WE. if from then on you see a high speed spitfire able to match the hun online, that be me and no begging for trade secrets will get me to reveal its method

ps: i do note what you said about the parachute effect reversing whatever speed gain might be created

[macro]

But you cant do what you said in reverse. If you leave rad shut the engine blows up. Got me all exited then when i saw title of thread.

[pstyle]

Originally Posted by ATAG_Dutch

'Open Cowling FULL before start engine and Do not close it!'
.

OK, So I've decided to test this little suggestion from Thomas Voss of Desastersoft:

I flew a spitfire 2a, with 50% fuel.
I've carried out testing at three altitudes >250ft, 5,000ft and 10,000ft.
I tested the airspeed at 2400, 2600 and 2800 RPM at each altitude.
Boost pressure was ALWAYS adjusted to read +5 in each case.
All tests were carried out with 100% open radiator
All speeds are indicated, at straight and level flight.
The ONLY variable was this - one test 1 I opened the radiator before starting the engine. In test 2 I waited until I was nearly airborne before opening the radiator.

SPEED test results:

http://postimage.org/image/mqaksad1v/

For me, there is NO obvious speed improvement resulting from opening the radio before engine start in the 2a.

[*Buzzsaw*]

Salute

Whether the OP was sincere or not, his suggestions are of no utility. Using them produces the same problems of lack of speed and climb. Any attempt to use +12 boost at 3000 rpm will destroy the engine almost immediately whether the rad is 100% open prior to takeoff or during flight. Any attempt to use the allowable continuous settings also results in short engine life.

So far the best suggestions put forward to maximize the engine life and speed of the British aircraft have been suggested by ATAG_Dutch, (ie. using max. 2650 rpm at 1/2 rad opening at full boost, and 2400 rpm and 1/2 rad for cruising) see thread on this board) but of course, while his suggestions do remove the problems of overheating and engine destruction, they still do not result in the British aircraft achieving their historical top speeds.

[ATAG_Snapper]

Originally Posted by *Buzzsaw*

Salute

Whether the OP was sincere or not, his suggestions are of no utility. Using them produces the same problems of lack of speed and climb. Any attempt to use +12 boost at 3000 rpm will destroy the engine almost immediately whether the rad is 100% open prior to takeoff or during flight. Any attempt to use the allowable continuous settings also results in short engine life.

So far the best suggestions put forward to maximize the engine life and speed of the British aircraft have been suggested by ATAG_Dutch, (ie. using max. 2650 rpm at 1/2 rad opening at full boost, and 2400 rpm and 1/2 rad for cruising) see thread on this board) but of course, while his suggestions do remove the problems of overheating and engine destruction, they still do not result in the British aircraft achieving their historical top speeds.

+1

An interesting exercise we ran for a short time over on our trial Server #2 was to uncheck the Engine Temperature Management, but leave CEM checked (activated) per normal. We did this to evaluate the effects of radiator drag on overall aircraft performance (vs the same aircraft on the main Server #1 with ETM "on" per usual). Quite an eye opener. (Anyone can do this on their own PC in single player, or setting up their own server, if they choose).

Septic and I were running some tests, he flying an E4 with autopitch selected, myself flying the Spit 1a 100 octane. With ETM off the two fighters were evenly matched at top all-out speed at sea level (E4 - WEP, Spit - 3000 rpms/11 lbs boost). For mile after mile we skimmed the waves, wingtip to wingtip. Neither a/c gaining nor losing. On cue (via Teamspeak), we both hauled back and vertically zoom climbed, both engines still full out. As if in an airshow, the two a/c climbed side by each, then stalled and fell back at precisely the same time.

The 109 had the advantage in the dive -- I couldn't keep up, plus I had to cut throttle to avoid exceeding 420 IAS to avoid losing control services. In a sustained turn the Spitfire outurned the E4, took me approx 2.5 turns to get on Septic's tail. The fighting was exhilarating, the two of us are about equal in skill (yeah, yeah....."You can teach MONKIES to fly better than THAT!" LOL). We didn't shoot our guns so we could prolong the session ("Takka takka takka takka" -- over TS it worked fine. )

The downside to ETM turned off is the loss of realism (once it's fixed, that is) and the challenge of maximizing performance and keeping things cool. Add to that the DM in combat is compromised if coolant systems are hit by flak or bullets but doesn't affect the aircraft if ETM is off.

We didn't measure ROC of the two aircraft with ETM switched off, but that can easily be done offline by anyone who so desires. Our focus was on the overheating and excessive radiator drag on the RAF fighters.

Flying a Spitfire with the same sea level speed as the 109 made for some challenging and FUN dogfights, though!

[*Buzzsaw*]

Originally Posted by ATAG_Snapper

+1

An interesting exercise we ran for a short time over on our trial Server #2 was to uncheck the Engine Temperature Management, but leave CEM checked (activated) per normal. We did this to evaluate the effects of radiator drag on overall aircraft performance (vs the same aircraft on the main Server #1 with ETM "on" per usual). Quite an eye opener. (Anyone can do this on their own PC in single player, or setting up their own server, if they choose).

Septic and I were running some tests, he flying an E4 with autopitch selected, myself flying the Spit 1a 100 octane. With ETM off the two fighters were evenly matched at top all-out speed at sea level (E4 - WEP, Spit - 3000 rpms/11 lbs boost). For mile after mile we skimmed the waves, wingtip to wingtip. Neither a/c gaining nor losing. On cue (via Teamspeak), we both hauled back and vertically zoom climbed, both engines still full out. As if in an airshow, the two a/c climbed side by each, then stalled and fell back at precisely the same time.

The 109 had the advantage in the dive -- I couldn't keep up, plus I had to cut throttle to avoid exceeding 420 IAS to avoid losing control services. In a sustained turn the Spitfire outurned the E4, took me approx 2.5 turns to get on Septic's tail. The fighting was exhilarating, the two of us are about equal in skill (yeah, yeah....."You can teach MONKIES to fly better than THAT!" LOL). We didn't shoot our guns so we could prolong the session ("Takka takka takka takka" -- over TS it worked fine. )

The downside to ETM turned off is the loss of realism (once it's fixed, that is) and the challenge of maximizing performance and keeping things cool. Add to that the DM in combat is compromised if coolant systems are hit by flak or bullets but doesn't affect the aircraft if ETM is off.

We didn't measure ROC of the two aircraft with ETM switched off, but that can easily be done offline by anyone who so desires. Our focus was on the overheating and excessive radiator drag on the RAF fighters.

Flying a Spitfire with the same sea level speed as the 109 made for some challenging and FUN dogfights, though!

Salute

Interesting comparison. Sad story this cannot be replicated with using full engine management.

Historically, the Spitfire 100 octane and 109E4 should, to all intents and purposes, be almost identical in speed and climb at sea level up to approx. 15,000ft/5000 meters.

At altitudes over that where the higher boost on the Spitfire cannot be obtained, (over approx. 16,000 ft) the 109 should begin to gain an advantage in top speed and climb.

Turn should be to the Spitfire's advantage, but rollrate at dogfighting speeds, (approx. 200mph/350kph) should see the 109 be roughly twice as good in its lateral performance as can be seen in this test:



This would mean the tactic of choice for the 109 in dogfights, would be the scissors. At very high speeds, the rollrate advantage is reversed, with the Spitfire gradually gaining an advantage.

The 109 should show a better dive acceleration, this coupled with the advantage of being able to 'bunt' directly into a dive, instead of having to roll and dive, would allow them to escape most combats where the 109's have a decent amount of altitude under them.

Accurate modelling of the historical aircraft would see the historical tactics being repeated, ie. 109's coming in high where they have a performance advantage, above their bombers, with the Spitfires being scrambled and having to climb to altitude in most instances.

A lot of those who predominantly fly the German side will complain that modelling the historical Spitfire with its equal speed and climb and better turn will provide too much of an advantage to the British side. They are ignoring the fact that Spitfires were only 1/3 of the available Fighter types. 2/3's of the British single seaters were Hurricanes, which were considerably slower and showed a inferior climb to the 109 at all altitudes even when using 100 octane fuel. In addition, the Hurricane had a rollrate slower than the Spitfire, a 109 should be able to scissor extremely effectively with a Hurricane. As well, the Hurricane had a much inferior dive, with slower acceleration than the Spitfire and lower maximum dive speed. Unless a 109 pilot is foolish and ends up low and slow on the deck with an overheating engine, he should be able to exit any fight with a Hurricane at will. The Hurricane should be able to outturn 109's slightly more easily than the Spitfire, depending on the altitude of the combat, over the altitude where +12 boost can be used the Hurricanes should see gradually decreasing turn performance, something which would affect the Spitfires less, since their elliptical wings were particular effective in thinner atmospheres.

Correctly balanced Servers should see players restricted in the numbers of Spitfires which may be selected, (as well as 25% 109E1's present during the earlier phases of the battle, and negligible numbers of E4's prior to late September) thereby putting the majority of those in British aircraft in Hurricanes.

[Bounder!]

Originally Posted by *Buzzsaw*

Salute

Historically, the Spitfire 100 octane and 109E4 should, to all intents and purposes, be almost identical in speed and climb at sea level up to approx. 15,000ft/5000 meters.

At altitudes over that where the higher boost on the Spitfire cannot be obtained, (over approx. 16,000 ft) the 109 should begin to gain an advantage in top speed and climb.

Certainly agree that the Spitfire and 109 top speeds should be very similar, almost everything I've read seems to state that. Not sure about the 109 having a greater top speed at altitude or sustained climb though?

This graph (posted in this thread http://forum.1cpublishing.eu/showthr...=34115&page=10) showing top speed at altitudes ranging from sea level to 35 thousand feet seems to show the Spit having a slight edge on the 109 at altitude:

[*Buzzsaw*]

Originally Posted by Bounder!

Certainly agree that the Spitfire and 109 top speeds should be very similar, almost everything I've read seems to state that. Not sure about the 109 having a greater top speed at altitude or sustained climb though?

This graph (posted in this thread http://forum.1cpublishing.eu/showthr...=34115&page=10) showing top speed at altitudes ranging from sea level to 35 thousand feet seems to show the Spit having a slight edge on the 109 at altitude:

Your chart is for an E3, and secondly, it does not specify boost level for the engine. I do not think it is for an E3 using the potential boost allowable during BoB.

It is also more importantly not an actual German test document, but a chart derived from a couple of secondary sources.

And the Spitfire performance is noted as being 'slightly adjusted' by Alfred Price, based on a couple of assumptions which may or may not be accurate.

I would recommend you study the actual test charts available on this site:

http://www.wwiiaircraftperformance.org/

[Kurfürst]

Originally Posted by *Buzzsaw*

Correctly balanced Servers should see players restricted in the numbers of Spitfires which may be selected, (as well as 25% 109E1's present during the earlier phases of the battle, and negligible numbers of E4's prior to late September) thereby putting the majority of those in British aircraft in Hurricanes.

There were more E-4s around by late September than all Spitfire Marks combined...

On 31 August 1940, fighter units (excluding JG 77) reported>

375 E-1s,
125 E-3s,
339 E-4s
32 E-7s on strength,

Most of the E-3s had been already converted to E-4 standard.

By July, one Gruppe (Wing) of JG 26 was equipped with the Bf 109 E-4/N model of improved performance, powered by the new DB 601N engine using 100 octane aviation fuel.