Author Topic: Spitfire 14 is porked (Read 3913 times)

Arlo · « **Reply #30 on:** December 18, 2003, 02:30:14 PM »

Of course ... Izzie will read that and gladly make a concession if not an outright reversal in judgement that may reflect positively on something not of German manufacture, Nashwan.

Luftdweeb: Luftwaffe is da chit!

RAFdweeb: No ... you is da lie ... RAF is da chit!

AAFdweeb: No you both lie ... USAAF is da chit!

NAVdweeb: Unless you count the US Navy it's da chit!

Everyone to everyone: No you all lie you is da suck!

Everyone to everyone: Oh yeah?! Prove it that I is da suck and you is da chit!

(And the chart/graph/interpretation version of WWII continues)
[/B]

Kweassa · « **Reply #31 on:** December 18, 2003, 02:51:37 PM »

All german climb tests are flown with cooler settings at "climb flight settings"(steigflugstellung: half open at 220mm) up to the rated alt. Then changing from half open to "high speed setting"(schnellflugstellung: 65mm open) till 2500m to 3000m above the rated alt. From this point up to the service ceiling the radiator setting was fixed on high speed setting.

The power setting was at Steig&Kampfleistung.

...

The G-2 does 6000m(18k ft) at 5:45, and 7000m(21k ft) at 7:00 with 100% throttle and radiator flaps partially open. Maybe it's because AH planes don't overheat, don't have to worry about using emergency power at climbs, and the radiators are always considered closed, that the G-2 outclimbs Spit14 in AH.. who knows?

Kweassa · « **Reply #32 on:** December 18, 2003, 03:08:58 PM »

Oh, btw, either the climb test wrong, or HTC is lying - but AH data shows the Spit14 outclimbs the G-2, WEP or no WEP. Only when the Spit14 is running on normal power and the G-2 on WEP, does the G-2 outclimb it.

Hap · « **Reply #33 on:** December 18, 2003, 03:54:43 PM »

in offline test, g2 did not out climb spit 14

niklas · « **Reply #34 on:** December 18, 2003, 04:54:09 PM »

Quote

Originally posted by Nashwan
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.
Quote

BS. Why do you bring the same lie over and over again?
When the supercharger uses less revolutions, there remains more excess power on the prop shaft. The Spit14 in this test had a ~2000hp griffon up to 2k. See my picture to understand what would be a realistic climb rate with a reduction ratio that gives 9k critical alitutde. And this straight green line i drew is even optimistic, the realitic curve would run below it between 2k and 22k due to atmospheric conditions.

niklas

Arlo · « **Reply #35 on:** December 18, 2003, 04:59:04 PM »

Yeah! You is da biased. I is not da biased. My favorite plane is da chit! Yours is da suck![/b]

Furball · « **Reply #36 on:** December 18, 2003, 05:12:11 PM »

arlo, you are teh suckest of teh sux.

not to mention biased against everything

mold · « **Reply #37 on:** December 18, 2003, 05:18:59 PM »

We all know the only real conclusion that can be reached from this debate--

Arlo is d@ REAL chit!!11!1!

BTW niklas, although I do agree with the sentiment in your sig, I think it deserves a better wording: "The only good spitfire is a burning spitfire"

Nashwan · « **Reply #38 on:** December 18, 2003, 05:41:48 PM »

Quote

QUOTE]Originally posted by Nashwan
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.
Quote

BS. Why do you bring the same lie over and over again?

Niklas, before accusing me of lying and Bull****, perhaps you could read what I said, and more importantly THE POINT I WAS REPLYING TO.

GScholz said:

Quote
The climb table at fourthfightergroup states 5.1 minutes to 20k

To which I replied:

Quote
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.

The prototype with a lower critical alt undoubtedly had a better climb rate below that critical alt, which was about 2,000ft iirc. However, it undoubtedly had worse climb above that critical alt, compared to the production model with increased supercharger gear speed.

The production aircraft could maintain 18lbs boost up to 9,000ft, the prototype, which had a better climb rate below 2,000ft, had dropped to 12.9 lbs by 8,000ft.

To compare the climb rates:

The production aircraft reached 9,000ft in 1 min 56.5 secs. 9k to 14k should take 1 min 13.2 secs, 14k to 20k should take 1 min 37.6 secs.

That's 4 mins 47 seconds to 20k.

The prototype reached 20,000ft in 5.1 mins, which either means 5 mins 6 secs, or 5 mins 10 secs. Either way, it takes longer to get to 20,000ft than the production machine.

So when I replied to

Quote
The climb table at fourthfightergroup states 5.1 minutes to 20k

with

Quote
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.

I was 100% correct. You seem to have assumed I was speaking about the climb rate below 2,000ft, when I was talking about the overall climb rate up to 20,000ft, as was the quote I was replying to.

Nashwan · « **Reply #39 on:** December 18, 2003, 06:08:36 PM »

Quote

...and is that a Spit XIV with 150 octane fuel or not?

Those figures for the Spit XIV are with normal 100 octane fuel, at 18 lbs boost (or very close to it)

Edit: What happened to Squire's post?

Niklas:

Quote

When the supercharger uses less revolutions, there remains more excess power on the prop shaft.

I don't know anyone who'd argue with that. As to how much difference, I believe we argued that one already, and I don't have the energy to go over it again.

Quote

See my picture to understand what would be a realistic climb rate with a reduction ratio that gives 9k critical alitutde.

I'm not 100% sure what your point is here. Are you saying we should use your calculations instead of the climb chart we have for the production Spit XIV? I'd rather believe the actual tests, thanks.

However, there isn't that much difference between your calculations and the real test results. You seem to be showing about 4,550 ft/min up to 9k, the test results show an average of 4650 ft/min. Note, however, that the Spit on this test seems to be climbing a bit better than the prototype, in general. Where the prototype had a climb rate of 3,600 ft min, the production plane has 3,700 ft/min. Add the same 100 ft/min to the calculations you've done, and you arrive at the same figures the A&AEE did when they did the tests.

Angus · « **Reply #40 on:** December 18, 2003, 06:12:15 PM »

OOO-HOOOO warming up are we?

Hap:
"Oh, btw, either the climb test wrong, or HTC is lying - but AH data shows the Spit14 outclimbs the G-2, WEP or no WEP. Only when the Spit14 is running on normal power and the G-2 on WEP, does the G-2 outclimb it."

Don't know where to see that result, but a stopwatch brought me those results (error may be 3 secs or so, tops ):

Spit XIV, no wep, full load, with takeoff roll, 20K 6:46 Spit XIV, w. WEP, full load. with takeoff roll, 20K 5:50
in Real life this should be about 5 minutes, no WEP mentioned.
So the Spit XIV is definately porked. It actually gets outclimbed by the AH 109G2!
109G2 no WEP, full load,no gonds, with takeoff roll. 20K 6:34 109G2 w. WEP, full load,no gonds, with takeoff roll, 20K 5:48

Niklas:
I don't give doodly-squat about your quite advanced logistics about the gears and alt-bands, atmospheric pressure and so on. The fact remains. An EARLY production line Spitfire XIV of 8400 lbs climbed to 20K in 5 minutes/5 minutes 6 seconds in the test pilots first flight BTW... with NO engine overheating, using the boost of 18. Calculate as you want, this is a clocked test, (and probably a careful one regarding the engine). Wanna go to Newtons? Will make a quick calculation, but would LOVE to have a comparitive number from a different plane to 20K, hehe.

And Isengrim....a cookie for ya

"Expect that this "5500 feet climb rate" is a theoretical value, Angus. The dataset refers to a plane that had it`s radiators closed for the test. Nice trick Mike, not mentioning that, but anybody that reads the page for the JL 165`s trials at
http://www.fourthfightergroup.com/eagles/jl165.html

will find the reference to this "5500 fpm" Mk VIII test at +25 lbs boost by Vickers Armstrong, is doing 5580 fpm, but with radiator flaps closed. "

Well, will have to dig deeper to verify your statement about no other planes of this versions being able to close the radiator flaps
However, what an amazing test, climbing like that with the flap closed without harming the engine?!?!?!?!?......after all, that's what the plane did! And it kept on to what,,,,,20K+????
I'll look into it

Squire · « **Reply #41 on:** December 18, 2003, 06:18:52 PM »

Oops musta hit the wrong key.

Do we know what version the HTC XIV is supposed to have for fuel?

As to its turn rate compared to the IX I would expect it to be somewhat less at lower speeds due to the added weight, the test says same turning circle, but not at what speed and alt?

Angus · « **Reply #42 on:** December 18, 2003, 06:38:22 PM »

The test indicates a max turn "chase"

Nashwan · « **Reply #43 on:** December 18, 2003, 06:39:27 PM »

Quote

Originally posted by GScholz
Hap, to test climb you should take off and imediately engage autopilot-level wait until the speed reaches climbspeed (175mph) and then engage autoclimb and the timer.

If you look at the A&AEE test of the Spit XIV, it's clear they either began the test staionary, or at wheels up, not at climb speed.

The table gives the time taken to reach 1,700 ft as 35 seconds, which equals a climb rate of just under 3,000ft/min. The plane was actually capable of over 5,100 ft/min.

If you assume a climb rate of 5,100 ft/min, 1,700 ft should take 20 seconds, which means 15 seconds wasted taking off/getting up to climb speed after takeoff.

Squire · « **Reply #44 on:** December 18, 2003, 06:46:19 PM »

Well they have different corner velocities, and they also bleed energy at different rates, so Im not sure what to make of that either. I have no doubt the XIV could turn a hard corner, it should.