Aces High Bulletin Board

General Forums => Aircraft and Vehicles => Topic started by: agent 009 on February 03, 2006, 10:24:47 PM

Title: K-4 Last ones out. hey Kurf.
Post by: agent 009 on February 03, 2006, 10:24:47 PM

OK, couple K-4 things. last 140 that rolled out with 1.98 ata. Um, how fast?

& I read the dashboard was wood, I know tail & prop were too. What other parts were? & what were these supposed aerodynamic changes that made it 20 kph faster than G-10? is that myth?


, Adding 1.98ata/2000HP engine for the K-4, and possibly G-10.

This would present the 1945 version of the K-4, with increased performance below 7500m, and ca 20kph increase in speed and climb rate. This boost was cleared for the DB 605D in February 1945 after some delays, and were put into effect by an OKL order in March 1945, effecting 4 Jagdgruppes (fighter wings) of a total of about 140 aircraft.

& what does ata mean?

Title: Re: K-4 Last ones out. hey Kurf.
Post by: zorstorer on February 04, 2006, 02:56:36 AM

Quote

Originally posted by agent 009


& what does ata mean?

I think it means atmospheres...meaning 1.98 times normal (absolute) amosphere pressure (14.something PSI)


Then again I might be totally wrong :)

Title: K-4 Last ones out. hey Kurf.
Post by: justin_g on February 04, 2006, 05:31:28 AM

1 ata = 1 kilogram per square centimetre(aka: technical atmospheres) = 0.968 standard atmospheres, 28.96 in Hg, 14.22 psi...

Title: Re: K-4 Last ones out. hey Kurf.
Post by: HoHun on February 04, 2006, 07:21:17 AM

Hi Agent009,

>what does ata mean?

ata = atmosphere, technical, absolute.

This makes it diffferent from

atü = atmosphere, technical, difference pressure.

atü was used for stuff like tyre pressure, oxygen pressure and air pressure on Luftwaffe aircraft.

ata was (pretty much exclusively) used for boost bressure.

1 ata = 0,980665 HPa = 735,6 mm Hg = 28,96" Hg

In British terms, 1 ata is equivalent to -0,4690 lbs/sqin boost because the British gave boost as a difference pressure and not as an absolute pressure as most other nations. (I believe the Japanese used difference pressure, too, measuring it in mm Hg.)

Regards,

Henning (HoHun)

Title: K-4 Last ones out. hey Kurf.
Post by: justin_g on February 04, 2006, 09:20:42 AM

Russians used same system as Japanese too.

Title: K-4 Last ones out. hey Kurf.
Post by: Bruno on February 04, 2006, 09:26:27 AM

ATA * 28.96 =  InHg

(PSI * 2.04) + 29.92 = InHg

Here's a conversion chart

(http://img40.potato.com/loc154/th_2bb54_BoostConv.jpg) (http://img40.potato.com/img.php?loc=loc154&image=2bb54_BoostConv.jpg)

1.98 * 29.96 = 57.34 inHg / 13.44 PSI

Title: K-4 Last ones out. hey Kurf.
Post by: agent 009 on February 04, 2006, 01:37:06 PM

OK, cool. Then were these last K-4's the 452 mph ones? or perhaps even better? or not.