Low ATA at high altitudes?

[Nealius]

I can't find this mentioned in the DCS manual or Chuck's Guide, and it's radically different from the Jug, Mustang, and Spit where max manifold pressure is still achievable at high altitude.

 

8km in an unladen Fw190, supercharger kicked in at 3.3~3.5km as normal, prop pitch auto, throttle max, RPM 2700. 

 

But I'm only getting 1.21 or 1.22 ATA at max throttle. Even the AI Antons are outrunning me at the same altitude. It's almost like the hi blower stopped working at some point. 

 

Is this normal or am I missing something? 

[saburo_cz]

Critical altitude for 1,42ATA is roughly at 6650 m, for horizontal flight. It is in DCS.

Data from real test shows similar result (actualy slightly below).

 

During climb critical altitude will be much lower, will depend on actual speed.

[grafspee]

This is why FW190 changed in to Jumo 213, BMW801 high alt performance was poor.

At what alt you get 1.2 ATA, take note that once you reach critical alt ATA drops quite rapidly, at 8km ATA may drop to 1, but i haven't flying Anton that high. This is not plane for this role.

Edited September 14, 2021 by grafspee

[Nealius]

That's interesting. I thought it was often used for high altitude bomber intercept. It performs quite poorly down low for me, with high energy bleed, low acceleration, and poor climb performance. What role was it intended for? 

[grafspee]

As far as i know A-8 was much more of the ground attacked then early versions of Anton, from era of spitfire MK V it was formidable fighter after introducing MK IX and P-51 not so much :)

[Nealius]

The F-8 is supposed to be the ground attack role, though. 

[grafspee]

18 minutes ago, Nealius said:

The F-8 is supposed to be the ground attack role, though. 

As you can see A-8 performance compare to late set of allied planes isn't projecting happy ending   It is out classed by P-51 by a large margin, it is a bit faster then Spitfire but speed advantage is negligible at this point because is very small.

A-8 would be a good plane for shooting down bombers but allied air force introduced full bomber fighter escort, A-8 become not a option then.

Edited September 15, 2021 by grafspee

[Nealius]

So by '44 they were taken off the anti-bomber role completely? 

[grafspee]

14 minutes ago, Nealius said:

So by '44 they were taken off the anti-bomber role completely? 

Just imagine A-8 fighting P-51 B/C at high alt  It would be mayhem.

I don't know, A-8 definitely wasn't up to the task by 44 but this does not mean that wasn't used in that role. 

ED kind of miss lead ppl about German fighters performance by introducing D-9 and K-4 those were late 1944/ early 1945 planes,

G-6 had similar full throttle height as Anton so P-51 at alt 30k ft was far superior, this is why all reports saying that P-51 could out turn everything what Germans had, most of the experience came from bomber rides engagements, US and UK did a lot of bombing runs  

K-4 and D-9 production numbers were just water drop in the sea compare to overall german fighters production.

Edited September 15, 2021 by grafspee

[saburo_cz]

2 hours ago, Nealius said:

So by '44 they were taken off the anti-bomber role completely? 

They were use as a main anti bomber plane until war end.

[Bremspropeller]

On 9/15/2021 at 6:29 AM, grafspee said:

As far as i know A-8 was much more of the ground attacked then early versions of Anton, from era of spitfire MK V it was formidable fighter after introducing MK IX and P-51 not so much

 

The A-8 was still a standard run of the mill fighter version. The airframe had been standardised to implement several modifications to branch off into the F-8 (Schlachtflugzeug) and G-8 (Jabo). On top, you could bolt on a royal duckton of armor and make it a Sturmbock.

 

The A-8 could only haul stuff on the belly-rack. An F-8 would get underwing racks for 2x 50kg (or 2x 70kg), while the G-8 could haul a 250kg bomb under each wing.

To make things interesting, the G-8 was then kind of discontinued and an F-8 Rüstsatz took over that role. The F-8 and G-8 each had different weapon and armor-configurations. Instead of the cowling guns, the G-8 carries additional oil, as it could also carry 2x 300l tanks (one under each wing).

 

The A-8's basic airframe was still a good fighter. What it lacked was a proper supercharger for higher altitude performance. The D-9 basicly had the same power and slightly better altitude characteristics and it already improved the airplane by quite a bit. The D-13 was on the horizon when the war ended and it offered completely on-par performance with the western allied aircraft. That's mostly just by swapping onto the Jumo 213F/ Jumo 213EB with a contemporary supercharger system. That's a two stage three-speed design.

[iFoxRomeo]

The A8's ATA curve:

[Davee]

On 9/14/2021 at 9:19 PM, Nealius said:

That's interesting. I thought it was often used for high altitude bomber intercept. It performs quite poorly down low for me, with high energy bleed, low acceleration, and poor climb performance. What role was it intended for? 

A8 version designed for ground-pounding. An A4, A5 or A9 would give better AA performance.