Climb rate vs climb speed - A case study of an interception

[Lusche]

A few days ago I was in a short dispute on country channel. I made a remark that I was chasing down a flight of B-29s at 26k in my 262, to which someone replied I should have taken a Ta 152 for it's better high altitude performance.
When I said that in this case I would never have caught the B-29s, I was drawing huge criticism by players bringing the "I have shot down (a lot) of 29's in the Ta 152", implying that I'm doing something wrong.


I think an explanation of this sortie and the choices behind the plane selection can highlight how much broad statements and "common knowledge" can fail to apply to special situations.

Tactical situation: A friendly base showed a single, rather fast moving con on dar, apparently heading for the town. By jumping into a 88 mount (to utilize the increased icon range) I found out that the con was a formation of B-29's, moving at an altitude of 26-27k (3x read icon range= distance in feet, adjust for horizontal displacement of the con). A juicy, but very diffcult target, particularly as it really turned out to be a town buster - unlike strat raiders they have a quite unpredictable route, which can easily changed  in response to interception attempts.

27K is indeed Ta territory, which has much better handling over the Me 262 at that altitude. On top of that, the Ta 152H has a significantly higher rate of climb



So why would someone chose the Me 262?

Because of the climb speed - the (mostly) horizontal speed of the airplane while climbing!
The B-29 travels terribly fast at altitude. While a fighter climbs up, it can cover huge distances. Thus a fighter chasing a B-29 can find himself dozens of miles behind his prey, making a successful interception very difficult or even impossible. A Ta 152H has a default climb speed of 169mph, the Me 262 about 300mph. This results in the following climb profiles:


(Data points in the chart are plane positions by every minute)

While the Ta takes only about 10 minutes to get to the B-20's flight level and the Me 262 5 minutes longer (50%), it would end up one sector behind the B-29s, doing ~260mph. It would have to accelerate for a long time before it would actually start to close in on the B-20 (which was making more than 360 mph at that time). And the distance of one sector would mean the Ta would not be able to detect changes in the Superfortress course quick enough, unless the change was made inside a friendly working radar circle.
The Me 262 would take 15 minutes, but would arrive at almost 430mph (already faster than the 29) and having been within dot range most of the time.

And was is the sole advantage of the 262 which made it a better 29 hunter in this or, similar situations: The ability to keep the Superfortress in visual range while climbing.
If you are able to take off in advance, ahead of the B-29, or if you just happen to be at high altitude when running across a B-29, a Ta (or other planes like the P-47s) might be a much better choice.  But this wasn't possible in this case, as the bombers route was unclear and the 'cruise' speed was very high.


The actual sortie came out as a draw: I was able to catch the B-29 formation and shoot down one bomber, before the buff pilot did the right thing and pulled up. At that altitude I couldn't follow his climb for long (particularly as I somewhat botched the recovery after my first attack).
Lusche 1, enemy 0 with 2 surviving planes.

[Wiley]

Makes sense.  Obviously you're not going to get the same profile from a prop plane, but what would happen if you didn't autoclimb the 152 and kept its horizontal speed higher?  Could you achieve similar climb rate to the 262 with a reasonable amount of horizontal speed?

Not sure how one would go about doing that other than manually.

Wiley.

[Lusche]

Makes sense.  Obviously you're not going to get the same profile from a prop plane, but what would happen if you didn't autoclimb the 152 and kept its horizontal speed higher?  

If you set the climb speed to the same value as the 262 has, the rate of climb will drop to less than 50% - A mere 1600f/min near sea level, over 10k it already drop below 1000ft/min. WEP will run out at 12k.

[Wiley]

If you set the climb speed to the same value as the 262 has, the rate of climb will drop to less than 50% - A mere 1600f/min near sea level, over 10k it already drop below 1000ft/min.

Maintaining the same speed as the 262 I don't think would work well.  You're just not going to beat a jet with a piston plane.

What I'm wondering is, if you manage the climb to match the climb rates of the 262 somewhat, can you get there in perhaps a bit longer time, but still having the better high alt performance of the 152?

I've done somewhat similar things in a jug, managing horizontal versus vertical speed without really thinking about the numbers.  I wasn't coming up straight under them, I knew they were there and upped a bit ahead of them.

Edit:  Just to be clear, not saying you're wrong, it's just looking at the two curves it seems like one might be able to get there fairly close to the same amount of time, with more capability at alt with the 152.

Wiley.

[Lusche]

Maintaining the same speed as the 262 I don't think would work well.  You're just not going to beat a jet with a piston plane.

What I'm wondering is, if you manage the climb to match the climb rates of the 262 somewhat, can you get there in perhaps a bit longer time, but still having the better high alt performance of the 152?

I'd say it wouldn't work out well. While you still couldn't keep up enough speed to keep the B-29 within icon range in the scenario presented above, you will still lose a lot of your climb rate. In other situations, against bombers with a slower cruise, it can be be the right thing to do.
But against a B-29 at very high altitudes, you really have to plan ahead and go for a point of intercept way ahead of the current position of the Superfortress, weppin' your way up to the stratosphrere (kinda).

I was hunting high alt bombers quite often in the 262 for years, but only the B-29 made me use it in a way I previously had done only with planes like the Bf 109 or Ta 152, becasue of that huge differential between bomber cruise and fighter climb speed.

[Wiley]

Yeah.  You're probably right.  It just seems in broad terms like there is a bit of wiggle room for preference for climb rate vs horizontal speed vs ability to maneuver once you're there.  I believe you're right though, nothing other than a jet is going to be able to take off from directly below the B29 and stick with it up to the point of shooting it.

Better to just forget about all this, take off way ahead of em and loiter.

Wiley.

[Zoney]

Better to just forget about all this, take off way ahead of em and loiter.

Wiley.

You called ?

[Karnak]

I lost a Mossie XVI to a Ta152 and an Me262 on Saturday, but I was doing a  "role-play" mission to the "Big City" and per such I didn't think it proper for me to use the dar bar to tell me somebody had lifted in pursuit and that somebody had lifted near the city so I continued my attack.  I hit the city with a 'cookie' and made it about 30 miles north of the city before the Ta152 was able to intercept me at an altitude of about 35,000ft.  The Me262 was about 2-3000ft below me and showing an icon range of 2.0.  In the ensuing fight I was gradually picked apart by the Ta152, the Me262 never managing to get a gun solution.  I list an aileron on the second or third pass by the Ta152, my #2 engine's oil was hit on the next pass and my #1 engine's oil a couple of passes later.  When one of my engines finally failed I was at about 10-15,000ft and at that point, being an role-play sortie, I bailed out of the stricken Mosquito.  I actually enjoyed the whole thing quite a bit.

I don't think the Me262 could have gotten me without the Ta152 being there and I don't think the Ta152 could have gotten me if I hadn't been committed to bombing the city.

Better to just forget about all this, take off way ahead of em and loiter.

Wiley.

That only works when you can tell where they are going and they are committed to going there.  See above.

[Wiley]

That only works when you can tell where they are going and they are committed to going there.  See above.

It's not 100% to be sure, but reading bar dar, dot dar, and flashing bases can make for some interesting sorties at ludicrous alt.  Once you get the later jugs/152 up there, it can cruise forever and you can run most things down.  Sometimes they do outfox you though.

Obviously seeing the enemy bardar coming and aborting the mission will get you out ahead of them.

Wiley.

[Karnak]

Well, it isn't aborting the mission so much as choosing to bomb a different town.

[Wiley]

At alt and up to speed, with reasonable map reading/enemy predicting ability a jug/152 can get you where you need to be pretty quickly.

I rarely see XVIs that high, so maybe they're a different kettle of fish, but in my experience with a little luck anything with 4 engines can be run down in a jug at ludicrous alt.

When I have seen XVIs, they were generally in the mid 20s and I got 1 pass as they blew through unless I had a bunch of smash.

Wiley.

[Zoney]

jug at ludicrous alt.
.

Wiley.

You called ?

[Karnak]

At alt and up to speed, with reasonable map reading/enemy predicting ability a jug/152 can get you where you need to be pretty quickly.

I rarely see XVIs that high, so maybe they're a different kettle of fish, but in my experience with a little luck anything with 4 engines can be run down in a jug at ludicrous alt.

When I have seen XVIs, they were generally in the mid 20s and I got 1 pass as they blew through unless I had a bunch of smash.

Wiley.

28,000 is the best speed alt of the XVI and that is the altitude I came in at.  I only went up to 35,000 in an effort to get above where the Me262 could get.  I think I would have succeeded too if not for the Ta152.  The Me262 was clearly struggling.

[Lusche]

28,000 is the best speed alt of the XVI and that is the altitude I came in at.  I only went up to 35,000 in an effort to get above where the Me262 could get.  I think I would have succeeded too if not for the Ta152. 

You certainly would have. I have been on both sides of that matchup more than once. The Mossie is well capable of outclimbing a Me 262 at that altitude. My enemy flying the 29 could have done the same (he had already dropped al his bombs), as he demonstrated by doing so, but only after I killed his lead bomber.

[Lusche]

I rarely see XVIs that high, so maybe they're a different kettle of fish,

In my opinion, the Mossie is even more than the B-29 currently a plane looking for a job in Aces High.