Spitfire LF Mk IX overperforming

Tested with WTRTI, the Spitfire LF Mk IX can sustain a climb rate of over 31.5 m/s (6200 ft/mim) at 0m altitude with a 25min fuel load.

The following source shows that with radiator shut, an RR Merlin 66 Spitfire LF Mk IX operating at +25lbs boost with 150 octane fuel achieves a climb rate of 5740 ft/min (29.2 m/s)
http://www.spitfireperformance.com/jl165.html

Here is another source claiming the same data

The aircraft tested in the above source has a weight of 3281kg. With 25m of fuel, the Spitfire LF Mk IX in game weighs 3288kg, so it not fair to claim that the lower performance figures are due to the irl tested aircraft carrying more fuel and hence being heavier.

Furthermore, I think the Spitfire LF Mk IX would fit Air RB better if it was given +18 lbs boost (around 1700 hp) and moved to 5.3.

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If you want to bug report it, may take time and lots of sources to get it right.

“EmptyMass”: 2960.0,
“MaxFuelMass0”: 289.0,
“OilMass”: 22.67,
3271kg

You should do it on total fuel for good measure.

It is over-performing, and a full fuel test puts the nail in the coffin:

I don’t get why people admitting they made a mistake annoys people… don’t people want others to fix mistakes?

Original post for transparency BTW. It proves the post didn’t change meaning.

Spoiler

image

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You have forgotten the weight of water (all liquid cooled planes have water), ammunition (varies) and the pilot (90 kg for all planes).

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Either way his test was way too light for my preference. I want to see the test, and I want it obvious.

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Screenshot_20240903-092504_Chrome

Except the graph states 7234 lbs, not 7400 like you showed.

Screenshot_20240903-092359_Chrome

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Neither site has that mass.
It’s either 7400 or 7450 pounds.

On top of that, pilot is irrelevant from these loads as they’re loaded without pilots.

The graph OP posted comes from the second website. I found it in 1 minute and I’m on my phone. It’s the section for testing of Spitfire J.L.165.

The graph directly states 7234 lbs as my screenshots have already showed.

“All up weight” is the plane fully loaded for flight. This includes a pilot.

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What a meaningless reply. I’ll add my own.

MFW I edit my comment after the fact to try to win the online argument.

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After checking the sources further there are two tests using Spitfire J.L.165 here.

  1. Tests by Aircraft and Armament Experimental Establishment
  2. Tests by Rolls Royce.

The tests by the “A.& A.E.E.” were conducted with a weight of 7400 lbs, while those of Rolls Royce were conducted with a weight of 7234 lbs.

The values of the “A.& A.E.E.” are unsurprisingly lower (5080 ft/min, 25.8 m/s, at sea level, on the low altitude “Moderate Supercharger” gear, with full throttle), not only because of the increased weight, but also because climb rate tests were ran with fully open radiators.

However, in section 4.4, they use test results conducted by different groups, not only to compare different aircraft (a Spitfire Mk VIII tested by Vickers Armstrongs Ltd.) but also different tests done with Spitfire J.L.165, directly comparing the results obtained by Rolls Royce and the “A.& A.E.E.”.

The agreement between the Rolls-Royce and A.& A.E.E. performance figures is quite reasonable though the speeds particularly are much lower than those obtained by Messrs. Vickers Armstrong on the other aircraft.

The full report of the Rolls Royce tests includes a table which directly states 5740 ft/min climb rate at sea level. As we already know, the Rolls Royce tests were conducted with 7234 lbs of weight, and closed radiators.

table

The graph is provided at the end of the report and is easy to understand.

Each square is equal to 20 ft/min of climb (climb rate values come in intervals of 200 ft/min, with 10 squares between them).

So the graph also shows 5740 ft/min of climb rate at sea level.

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Nah not this guy again ;)

Dont ruin it before i get to spade it

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Yet he brings real, reputable sources. As usual, you bring nothing but unbased claims.

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@PercussionCap You responded to the wrong post.
His post misrepresented the sources in his post, sources I myself cite.
Wrong weight for the tests with parameters, used parameters from a graph without testing standards… or worse testing standards from one of the two articles.
So yeah, just cause his post made unbased claims doesn’t mean everyones’ did.

Keep claiming the sources are wrong, PercussionCap.
All you do is prove my posts correct.

Nope, as FlipAllTheTables put it, his claims are in line with the test.

image
“all up weight” matches what he tested with.

Prove that graph has parameters such as but not limited to radiator position, and prove that Blitz used those parameters.

image

The IRL test was with radiators closed. If OP also tested with radiators closed, the best case scenario for this, then the LF Mk IX is STILL significantly overperforming.
If OP had the radiators open, obviously then the climb rate achieved would be lower than if they were closed, and the LF Mk IX is overperforming even more.

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There is no citation for the definition of all up weight.
Currently there are no citations for War Thunder’s pilot and ammunition mass regarding Spitfire LF Mk9.
And without citations, you must use the data available.
He’s objectively running the aircraft lighter.
Someone gave a claim without evidence of pilot mass.
58kg of the 50 cal LF Mk9 is allegedly ammo.
22.67 is liquids unless I find evidence water is separate from oil.
2960kg is empty weight.
3040.67kg.
241kg is missing, and there’s no citation of War Thunder’s pilot mass.

I’m going to run empty guns in one of my tests and add on the 58kg as fuel, just to remove a potential variable.
We still don’t have pilot weight though.

Let’s use the tools that WarThunder provides us.

image

That’s with 25 minutes of fuel. 3287 kg of weight.

In other words, you’re wrong.

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Prove that we’re all wrong.
All you’re doing is proving me and everyone else correct.

“All up” implies that’s what it took off with, so pilot is accounted for. Otherwise there is no point to recording this data if you’re not gonna use a real configuration.

He isn’t, that’s the weight they tested the aircraft at, and is the same standard that has been used in many bug reports - graph says X weight, you test it at X weight. From there it doesn’t really matter where your weight comes from, just that it’s there.

Who is “everyone else” here?

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