Author Topic: Tiffy (Read 749 times)

Kev367th · « **on:** July 01, 2004, 07:26:55 PM »

Sort out the Tiffy please. It is at least 14mph slower @ 6k than it should be, p51 is 5-10mph faster @ 6k than it should be. At the moment the P51 has a 2mph advantage at 6k over the Tiffy.

Witnessed by Steve who in a equal e state, and equal alt as my tiff chases me to deck me wep him none, and he catches relatively easily.

Why not turbo charge the 51 also while your at it, you've done so much else to make it the uber plane in here.

J_A_B · « **Reply #1 on:** July 01, 2004, 07:55:59 PM »

Quote

Sort out the Tiffy please. It is at least 14mph slower @ 6k than it should be, p51 is 5-10mph faster @ 6k than it should be. At the moment the P51 has a 2mph advantage at 6k over the Tiffy.

Ok...let's play along here. Start witht he P-51's +2 advantage....then -10 as he suggests...than +14 to the Tiff as he suggests.....

So....you think the Typhoon should have a ~20 MPH speed advantage over the P-51 at 6k? That's what your math adds up to anyway.

This begs the question--WHICH P-51? AH has two and they have decidedly different levels of performance at 6k, with one of them being noticably slower than the typhoon at 6k, and the other being about even.

J_A_B

Kev367th · « **Reply #2 on:** July 01, 2004, 08:42:00 PM »

Lets play then ... look at stats on ANY site Tiffy is faster than P51D @ 6k by around 14mph. Not slower as in AH2, and thats allowing for dive to 6k in P51D case, otherwise its max speed is around 350 not the 360+ ish it is here. Tiffy should be at 374. It should have a 14mph+ ish advantage at 6k.

J_A_B · « **Reply #3 on:** July 01, 2004, 09:18:27 PM »

"Tiffy should be at 374."

"Sort out the Tiffy please. It is at least 14mph slower @ 6k than it should be"

374-14 = 360.

So I therefore surmise that your Typhoon in AH2 had a top speed of 360 MPH at 6,000 feet.

I consider myself to be a pretty reasonable person. So, to give you the benefit of the doubt, I went and flight-tested the AH2 Typhoon at 6K.

Climb to 6K, level off (no diving to accelerate). I reached a speed of 393 MPH in level flight before I got bored and quit. If I was more patient I probably would have squeezed a couple more MPH out to make it an even 395.

If you can only get 360 out of the Typhoon in AH2 at 6K, while I can make over 390 with no difficulty, then somehow you are FLYING MORE THAN 30 MPH SLOWER THAN THE AIRPLANE IS CAPABLE OF.

Considering that, I have absolutely no doubt that a P-51 caught you with ease. I would suggest double-checking your control setup; perhaps your throttle isn't maxing or you RPM isn't at full.

I would also suggest looking for better sources than "web pages". "Web pages" are notorious for being inaccurate. Your numbers for both the P-51 and the Typhoon both look right--but for earlier models of the aircraft in question.

J_A_B

Kev367th · « **Reply #4 on:** July 01, 2004, 10:23:46 PM »

Will try recalibrating joystick yet again to see what happens.

Steve · « **Reply #5 on:** July 01, 2004, 10:40:52 PM »

I did seem faster on the deck Kev.. on the final reversal before our sprint to the deck I seemed to gain an angle and felt like I was more energy efficient than you, it's what encouraged me to keep chasing. I still agree w/ your basic analysis, that the pony seemed faster. BTW, how much fuel did ya have?

Kev367th · « **Reply #6 on:** July 01, 2004, 10:43:54 PM »

OK tried recalibrating.
P51D 25% fuel
Tiff 50%
Should be somewhere round equal?

Took off A1, slight lsft turn due east, climb to 6k and level
Record speed after approx 26 miles.

Results
P51D 381 mph !!!!!!!!!!
Tiffy 373 mph

Tell me thats right, in fact show me thats right.

That puts the P51D 21mph faster @ 6k than anything I've seen, from a gentle dive to 6k.
26 - 31mph faster at 6k doing a climb and level.

Looks like most other planes becoming a waste of time especially considering the 2x fuel burn.

Steve · « **Reply #7 on:** July 01, 2004, 10:49:05 PM »

Interestingly, I checked one web page for top speeds and found that they listed the Tempest top speed as 435MPH
They listed the P-51D as 437 top speed. Interesting stuff.

http://www.aviation-history.com/hawker/typhoon.html

Kev367th · « **Reply #8 on:** July 01, 2004, 10:59:32 PM »

It is just for giggles tries it with LA7 and Tempest

LA7 - 382 (just)
Tempest - 404 (just)

So somethings outta whack.
Wouldn't expect a P51 to be only 1mph slower than LA7.

Your figures are at 17k not 6k.

At 17k would expect Pony to be faster was designed for higher alts.
Bet we have a hybrid 51, the low level performance of original with high performance of latter. Seem to recall (might be wrong) that the orignal with Allison engine had oustanding low level performance.

J_A_B · « **Reply #9 on:** July 01, 2004, 11:55:54 PM »

All I can ask is--what are you doing wrong with the Typhoon?

I tested it again....and then again. I even went so far as to verify it with the film viewer after recording one test flight.

I could reach 393 MPH at 6,000 feet with no difficulty in the Typhoon. Repeatedly, and on film (not like anyone reading this can't test it in 5 minutes on their own). The in-cockpit Air Speed Indicator is actually wrong slightly and showed my speed to be about 396, howver this is a discrepency of less than 1 percent. 393 is the figure I'll quote since its the worse of them.

Interestingly, I am making that speed with twice the fuel load you took. I did my tests with 100% internal fuel because that represents how the REAL airplane would have been flight-tested. Weight can do some funny things with airspeed, so perhaps you should go back and try it with a full load of fuel.

Even its indicated airspeed at 6K was higher than the 373 you claim it capable of.

----------------------

I submit that you shouldn't worry so much about the P-51. You seem to hate it and are in fact spending more time complaining about it than your apparent difficulty in reaching the Typhoon's best speeds--which is the real issue.

Some clarifications:

"Wouldn't expect a P51 to be only 1mph slower than LA7. "

Why not? The LA7 only has a speed advantage at very low altitudes; above 5K they're almost even and by 7500 feet the P-51D has a clear advantage. It has been that way since the LA7 was released a couple years ago, so I don't see why it would "surprise" you that they're about dead even at 6k.

"Bet we have a hybrid 51"

No. In fact, we have two of them--the P-51B and the P-51D. The P-51B is best at high altitudes, and the P-51D performs fairly well over a wide altitude range. The Allison-engine P-51 you refer to is vastly inferior to the Merlin Mustangs at any altitude.

----------------

"So somethings outta whack. "

Yes--for whatever reason you aren't getting full speed (not even close) out of the Typhoon, and you're "barking up the wrong tree" as the saying goes.

J_A_B

MetaTron · « **Reply #10 on:** July 02, 2004, 12:28:40 AM »

Kev, the number one way to obtain E, while running on the deck, is to trim the elevator yourself, and not for level. The guys that fly the Tiffy most will catch a Pony on the deck easily.

straffo · « **Reply #11 on:** July 02, 2004, 12:36:46 AM »

Perhaps a stupid question but Kev do you have any external loadout ?

The rocket rail for example reduce the speed by about 10 mph

Btw I don't forget you ,I should post the panel pict today.

according to http://kingcat.hihome.com/speedgraph.html

it should be pretty even at 6K

Kev367th · « **Reply #12 on:** July 02, 2004, 03:20:24 AM »

Thanks Straffo, but Waffle posted some pics on the skins site. Never imagine a Tiffy had so many rivets lol.
Gonna finish the skins then try out the 51 for a while.
Should be ready sometime this weekend, fingers xssed.

J.A.B. I'll try it with a full fuel load as suggested. If it does go faster I have no idea what to make of that. You would imagine heavier aircraft - slower speed.
Or else everything would be flying at max all up wieght all the time.
Thanks for your help though.

Replicant · « **Reply #13 on:** July 02, 2004, 03:42:51 AM »

I don't think the straight and level speed of the Typhoon is a problem. The Typhoon doesn't accellerate that well and even an A6M can accellerate better than a Typhoon if coming from a shallow dive. The slight advantage of aircraft accelerating better, even in a shallow dive, will disadvantage the Typhoon until it reaches about 450mph+ (TAS) when it will then start to pull away. An La7 will always catch a Typhoon though, in my experience.

straffo · « **Reply #14 on:** July 02, 2004, 04:36:10 AM »

Quote

Originally posted by Kev367th
Thanks Straffo, but Waffle posted some pics on the skins site. Never imagine a Tiffy had so many rivets lol.
Gonna finish the skins then try out the 51 for a while.
Should be ready sometime this weekend, fingers xssed.

hehe

Perhaps you will reconsider it : http://www.onpoi.net/ah/pics/users/33_1088760868_typhoon.zip