Author Topic: Bob Johnson's observation of Luftwaffe fighters  (Read 2065 times)

Offline Widewing

  • Plutonium Member
  • *******
  • Posts: 8801
Re: Re: Re: Re: Bob Johnson's observation of Luftwaffe fighters
« Reply #15 on: November 26, 2003, 07:08:20 PM »
Quote
Originally posted by HoHun
Hi Widewing,

At this altitude, running at 64" Hg boost yielding 2600 HP, the P-47D referenced in this report achieves a speed of 438 mph. Increasing boost to 72" Hg and power to 2900 HP would give us a calculated top speed of 454 mph.

Still very impressive, but far from the 470 mph you mentioned.

(Just how far? Well, the P-47D in question would need no less than 3200 HP to get there. And my calculations actually neglect the transsonic drag rise that at these speeds begins to make itself felt.)


Heya Henning,

Then, how do you account for the P-47M-1-RE and P-47N-1-RE recording CORRECTED speeds of 475 and 467 mph respectively on 2,800 hp? These weren't massaged aircraft but fighters selected at random from the production line for testing.

My regards,

Widewing
My regards,

Widewing

YGBSM. Retired Member of Aces High Trainer Corps, Past President of the DFC, retired from flying as Tredlite.

Offline Pongo

  • Platinum Member
  • ******
  • Posts: 6701
Bob Johnson's observation of Luftwaffe fighters
« Reply #16 on: November 26, 2003, 07:48:43 PM »
Certainly it seems that the Jug pilots tore the experten heart out of the LW in the west.

Offline Halo

  • Gold Member
  • *****
  • Posts: 3222
Bob Johnson's observation of Luftwaffe fighters
« Reply #17 on: November 26, 2003, 08:12:53 PM »
Fascinating info, Widewing, thanks.  I've always been a Jug fan since as a little kid I used to watch them being test flown and their guns zeroed at the massive Evansville, Indiana, factory.
Luck is what happens when preparation meets opportunity. (Seneca, 1st century AD, et al)
Practice random acts of kindness and senseless beauty. (Anne Herbert, 1982, Sausalito, CA)
Paramedic to Perkaholics Anonymous

Offline Widewing

  • Plutonium Member
  • *******
  • Posts: 8801
Bob Johnson's observation of Luftwaffe fighters
« Reply #18 on: November 26, 2003, 10:53:17 PM »
Bob Johnson Interview: Part 1

A few months before Robert Johnson died (December 27th, 1998), I conducted nearly five hours of telephone interviews with Bob over the course of three weeks. I managed to record all but the first hour. During our conversations, we discussed the tactics he employed while battling the Luftwaffe. The following are some excerpts of our discussions.

CCJ: I have read an article about you and the tactics you used, that described you as one of the first fighter pilots to truly fight in the vertical plane.

RSJ: I don't know about that, there were others who fought that way.

CCJ: But not in the Thunderbolt....

RSJ: No, I guess not, at least when we first went operational.

CCJ: Can you describe how you used vertical maneuvering to your advantage, especially in the heavy-weight Jug?

RSJ: I think that you need to understand that everyone thought that the P-47 was a deathtrap. RAF pilots told us that we wouldn't have a chance against single-engine fighters. Those of us who had been flying the P-47 for a while knew otherwise, but there was nothing we could say that would convince the British, or the guys in the 4th.

CCJ: Guys of the 4th? You mean the 4th Fighter Group?

RSJ: Yeah. They were not at all happy trading in their Spitfires for the Thunderbolt.

CCJ: Didn't the 56th surrender their P-47s to the 4th after you arrived?

RSJ: Yes, we were told that we would be getting new planes.

CCJ: I'll bet that struck a nerve in the 56th.

RSJ: It sure did. We already had hundreds of hours in P-47Bs and Cs. No other group of pilots in the ETO had anywhere near our experience in the Thunderbolt. So naturally, we were not happy to hand them over to another Group. In retrospect, it was obviously a good idea. We realized as soon as we got into combat that there was no substitute for actual combat missions under your belt. Anyway, we trained the 4th on the Thunderbolt and then waited for what seemed like forever, to get our new planes.

CCJ: To get back to tactics, how did your tactics evolve?

RSJ: My tactics were rooted in what I had learned flying the P-47 in the States. We could always find some Navy Corsairs over Long Island Sound. We would bounce them, or they would try to bounce us. Usually, we had the advantage in height so the Corsairs were a lot busier than us.

CCJ: I take it that you seldom let an opportunity to jump them go waste?

RSJ: No, we usually went straight for them.

CCJ: Didn't they see you rolling in?

RSJ: Sometimes. We tried to use the sun to hide in. If they didn't spot us, we would lay it on them good. Their first hint that we were there was when we tore through them at high speed and zoomed back up above them.

CCJ: How did they react?

RSJ: They would usually scatter every which way. We would come back down on them again, but they would be alert now and break into us.

CCJ: I guess that is the point where it would break down into a big brawl?

RSJ: It did at first. The Corsair was just a fast as the Thunderbolt was around 20,000 ft., and it was very maneuverable. As we mixed it up and lost altitude, the Corsair became a real handful to outfly with our P-47Bs. I discovered that the Corsair pilots did not like fighting up hill. What I mean is, they would not or could not follow you if you pulled the nose up into a steep climb. I realized that the Corsair couldn't climb any better than the P-47, and would tend to spin out of a vertical stall. I also found that that any P-47, even the P-47B, could out-dive the Corsair. So that gave me two important advantages that I would use every chance I got.

CCJ: So these mock dogfights helped you learn how to exploit the inherent strengths of the Thunderbolt.

RSJ: Yes, very much so.

CCJ: What about facing the Fw 190 and Messerschmitts?

RSJ: The Focke Wulf reminded me of the Corsair. It was much smaller of course, but they both had similar maneuverability. It wasn't quite as fast, but turned well. It was unusual to find Focke Wulfs above us. Generally, we held the advantage in height.
The Me 109 was another story. They could often be seen up above 35,000 feet.

CCJ: What was the biggest mistake a German pilot could make?

RSJ: Trying to escape in a dive or split-S.

CCJ: Why?

RSJ: Because they were not going to out-run the Thunderbolt in a dive.

CCJ: You could catch them without a problem.

RSJ: I could catch them in nothing flat.

CCJ: Really?

RSJ: Absolutely. One thing about the 190, if the pilot continued his dive below 7 or 8 thousand feet, he could not pull out before he hit the ground. I guess they had compressibility problems or the elevators got too stiff. What ever the problem was, I watched several of them pancake in before they could level off.

CCJ: What about the Thunderbolt?

RSJ: It did not have that problem down that low. Up high, above 25,000 feet, yes, I could get into compressibility and the elevators locked up like they were in concrete. But once you got down to thicker air, you regained control.

CCJ: So, what would you do if suddenly discovered a German fighter on your tail?

RSJ: you mean in close?

CCJ: Yes.

RSJ: That depended a lot on how fast the German was going. If he was moving much faster, I'd simply side-step him by rolling.
The German would whiz right on by and I would firewall the throttle and take off after him. If he was a smart German, he would climb straight ahead. If he was a dumb German, he would try to turn. If he turns, his higher speed will make for a wide turn, and I will cut across and be all over him. If he dives, I can follow and eventually catch up. Now, if the German's speed was close to mine, then I had another emergency maneuver that always worked for me.

CCJ: And, that was?

RSJ: I would pull the nose straight up into a vertical rolling spiral, usually to the left. You would stall out, but so would the guy behind you. That killed his advantage.

CCJ: So, what you are describing sound like a rolling hammerhead stall, right?

RSJ: That's a pretty good description.

CCJ: So what happens next?

RSJ: Well, the enemy would stall first because the Jug's mass allowed to retain its,
er...

CCJ: Energy?

RSJ: Yes, energy. The P-47's mass allowed it to retain its energy better and it stalled a few seconds after the enemy plane. The German would snap over and head down. Except, now I was right behind him and there was no getting away.

CCJ: Wouldn't he still be directly behind you?

RSJ: No. Pulling up so suddenly always caught them by surprise. The second or two that it took for them to react took care of that.

CCJ: Why did you roll?

RSJ: Because that killed my speed faster than the enemy if he didn't, which gained me the advantage of being to his rear as he zoomed up. If he rolled too, that also worked to my advantage because it killed his speed faster than mine.

CCJ: So, you would get the advantage no matter what, if the German also pulled up into a vertical climb. What if he didn't follow?

RSJ: Then he would just fly by. If he still wanted to fight, he could extend out and turn around, but I would be waiting for him.
If he turned either left or right, I would be all over him in a few seconds.

CCJ: The smart Germans just kept on going when you pulled up.

RSJ: I never ran across one smart enough to keep going. They all tried to follow.

CCJ: How many got away after falling for your trap?

RSJ: I really can't say for sure. Some got away because he had friends to cover his tail. Besides, that maneuver was not so much to get him, but to prevent him from getting you. In that respect, it always worked.

CCJ: Much has been written about the incredible roll rate of the Fw 190. Was it as good as they say?

RSJ: The 190 rolled very fast. But, so did the Thunderbolt.

CCJ: But not as quickly as the Focke Wulf.

RSJ: I would say just as fast. I never had a 190 out-roll my Jug. Never.

CCJ: What about a situation where you end up in rolling scissors with a Focke Wulf? Do you follow him by reversing the turn too?

RSJ: No. Whenever you get into a series of reverses, the airplane tends to mush-out a bit when you reverse your turn. The Jug tended to mush a bit more than the 190. The way to avoid this was roll into the reverse.

CCJ: I'm not sure I follow you.

RSJ: Picture this in you mind. The 190 rolls into a hard left. You follow, firing as he crosses your guns. Suddenly, he reverses his turn, hard right. Rather than reverse, you continue rolling left until you are in a right bank, just like the 190. Now, pull hard. No mushing. If he reverses again, you roll left and fire as he crosses your guns. If he doesn't reverse, I pull the nose high and roll out behind him.

CCJ: A high yo-yo?

RSJ: Of a sorts, yes. Continuing the roll simply eliminated the mushing caused by reversing a turn and I would get a clear shot every time the enemy reversed.

CCJ: What you define as the most important things a fighter must know to be successful, relating to air combat maneuvering?

RSJ: It's pretty simple, really. Know the absolute limits of your plane's capabilities.
Know its strengths and weaknesses. Know the strengths and weaknesses of you enemy's fighters. Never fight the way your enemy fights best. Always fight the way you fight best. Never be predictable.
My regards,

Widewing

YGBSM. Retired Member of Aces High Trainer Corps, Past President of the DFC, retired from flying as Tredlite.

Offline Widewing

  • Plutonium Member
  • *******
  • Posts: 8801
Bob Johnson's observation of Luftwaffe fighters
« Reply #19 on: November 26, 2003, 10:55:08 PM »
The Bob Johnson interview: Part 2


CCJ: I remember reading where you thought that your P-47 was the fastest fighter in the ETO.

RSJ: I still believe that it was.

CCJ: Really?

RSJ: Sure. My second Jug, a D-5 was the best P-47 that ever flew, and I flew them all, including the P-47M which the 56th got near the end of the war.

CCJ: What made this one Thunderbolt so fast?

RSJ: Several things. My crew sanded every joint smooth, and waxed it to a high gloss. Factory technical reps showed my crew chief, Pappy Gould, how to adjust the wastegates to keep the boost pressure higher than normal. My D-5, which I named Lucky, had water injection. I never used the water injection in combat. I didn't need it. From time to time I'd switch it on, push the throttle up to 72" of manifold pressure and the head rest would smack me from behind. I would let her run for a few minutes just for the fun of it.

CCJ: 72 inches!? Did you ever take note of your airspeed during one of those runs?

RSJ: Of course.

CCJ: And....... how fast did it go?

RSJ: I've seen just over 300 at altitude.

CCJ: 300 indicated?

RSJ: Yes.

CCJ: What was your altitude?

RSJ: I guess it was right around 32,000 feet.

CCJ: Geez, that’s well over 450 mph!

RSJ: Oh, I figure closer to 470.

CCJ: Maybe you did have the fastest fighter in the ETO after all.

RSJ: Like I said, Lucky was the fastest.

CCJ: What ever happened to Lucky?

RSJ: She was lost in a mid-air collision over the North Sea. I don't recall the pilot's name who was flying her on that ramrod. I was very upset. Lucky got at least 24 enemy aircraft and was the best Jug I ever flew. She was trouble free and I never had a single abort while flying her.

CCJ: Bob, one final item before I let you go tonight.

RSJ: Sure.

CCJ: Is it true that you flew two 25 hour tour extensions after your 25th victory, and that you never were involved in a single combat during that time?

RSJ: Basically, yes. I took a 25-hour extension with the idea that as soon as I got 2 more enemy aircraft, I would stop there and go home. After the 25 hours were up and I hadn't had a chance to even fire at an enemy airplane, I took another 25 hour extension under the same understanding. Finally, on the last mission of that tour, I got two more and they sent me home.

CCJ: Why do you think that German fighters became so hard to come by at that time. When was that, in April and May of 1944?

RSJ: I can't say for sure, but we now know that the long range of the P-38 and P-51 caused the Luftwaffe to pull back many of their fighter squadrons deep into Germany. This makes sense when you think that we could put up over 600 P-47s for a ramrod. If they pull back beyond the range of the Jugs, we won't see much of them. Another thing was simple bad luck. When the Germans did come up to fight, they attacked the bombers well away from our assigned area. So, it really was a combination of factors.

CCJ: So, what was the date of your last two victories?

RSJ: May 8th, 1944.

CCJ: Well, Bob, I'll let you go now. Thanks for your time. This will make for a terrific article.

RSJ: It was my pleasure.

CCJ: Are you up for another discussion in a week or two?

RSJ: If you don't mind my long stories, sure. You can call almost anytime.

CCJ: Believe me, it's an honor for me. By the way, Art Heiden, you remember me talking about Art, Art wants to talk to you about Jack. Do you mind if I pass your number to him?

RSJ: Please do.

CCJ: Well, thanks again and have a good evening.

RSJ: You to.
My regards,

Widewing

YGBSM. Retired Member of Aces High Trainer Corps, Past President of the DFC, retired from flying as Tredlite.

Offline Batz

  • Gold Member
  • *****
  • Posts: 3470
      • http://bellsouthpwp.net/w/o/wotans/4JG53/
Bob Johnson's observation of Luftwaffe fighters
« Reply #20 on: November 26, 2003, 11:33:59 PM »
Quote
In contrast, there seems to be little doubt about Hans Phillipp. Johnson shot down a Bf 110, and then, alone, attacked four Fw 190s. He obliterated the lead 190. Most historians concur that the facts reported by the Luftwaffe pilots flying with Phillipp and Johnson's account are in agreement in detail as well as location and time of day. I believe that historians Raymond Tolliver and Trevor Constable discovered this and verified it as fact.

My regards,

Widewing


There is doudt and Johson's claim doedn't match up with the pilots flying with Philipp. They claim he was shot up and damaged by bombers and was on its way down when they lost sight. They claim the only way a p47 could have claimed a kill is if they chased after him.

In this same engagement Johnson was shot up (rudder cable)and and dove for home.

Quote
apparently Luftwaffe loss records, indicate that Herr Philipp was shot up quite heavily by the American bombers he was attacking. If any P-47 finished him off, it was while his plane was already descending and out of commission. So the German version


His wingman

Quote
On October 8, 1943, the 8th AF dispatched 156 bombers to targets in Bremen and Vegesack. The force was escorted by 250+ Thunderbolts from six different fighter groups.

The Stab Flight of the Geschwader heard Philipp announce a victory over a Thunderbolt. The last tranmission from him was: "Reinhardt, attack!" Feldwebel Reinhardt was Philipp's wingman on this day. He last saw the Kommodore's aircraft disappear in a cloud. Reinhardt was wounded after colliding with an enemy aircraft, but made a successful forced landing. Later that evening, the Geschwader learned that their Kommodore had been shot down and killed.


Johnson may well have shot him down but its not set in stone.
« Last Edit: November 26, 2003, 11:50:14 PM by Batz »

Offline HoHun

  • Gold Member
  • *****
  • Posts: 2182
Re: Re: Re: Re: Re: Bob Johnson's observation of Luftwaffe fighters
« Reply #21 on: November 27, 2003, 01:33:00 AM »
Hi Widewing,

>Then, how do you account for the P-47M-1-RE and P-47N-1-RE recording CORRECTED speeds of 475 and 467 mph respectively on 2,800 hp?

I haven't seen anything as detailed as the F4U-4 comparison report including the P-47M and -N (and after a quick look, some of my general books don't agree with the top speeds you quoted), so I'm unable to comment these figures.

Regards,

Henning (HoHun)

Offline gripen

  • Silver Member
  • ****
  • Posts: 1914
Bob Johnson's observation of Luftwaffe fighters
« Reply #22 on: November 27, 2003, 08:54:48 AM »
Here is couple NACA reports for additional info on R-2800. RM E6J08 is about pre-ignition limits with various fuels (28R is grade 100/130 and 33R is 110/145) and different spark-plugs (no water injection). Report 873 is about cooling of the R-2800 on high altitudes, it explains quite well why the P-47 tend to overheat at high altitude climbs. Overall it seems that 72" MAP might have been possible with right fuel (no water) but just for very short periods because overheating would have been pretty much instant without water injection.

Another interesting piece of data is ETO kill claim part of the USAAF statistical digest. Before January 1944 US fighters did not claim so many kills but after that claims steadily rise. Turning point appears to be the Big Week and after that claims still increased and continued in the same level until September. Basicly early P-47 operations did not affect a lot to Luftwaffe, seems that it was combined pressure on all fronts during summer 1944 which broke back of the Luftwaffe.

gripen

Offline Batz

  • Gold Member
  • *****
  • Posts: 3470
      • http://bellsouthpwp.net/w/o/wotans/4JG53/
Bob Johnson's observation of Luftwaffe fighters
« Reply #23 on: November 27, 2003, 09:16:22 AM »
Geesh

Total heavy bomber kills in the air 6,098
Total Fighter kills in the air 7,422

April 45

3,703 aircraft killed on the ground...........

Offline Widewing

  • Plutonium Member
  • *******
  • Posts: 8801
Bob Johnson's observation of Luftwaffe fighters
« Reply #24 on: November 27, 2003, 11:50:03 AM »
Quote
Originally posted by gripen
Here is couple NACA reports for additional info on R-2800. RM E6J08 is about pre-ignition limits with various fuels (28R is grade 100/130 and 33R is 110/145) and different spark-plugs (no water injection). Report 873 is about cooling of the R-2800 on high altitudes, it explains quite well why the P-47 tend to overheat at high altitude climbs. Overall it seems that 72" MAP might have been possible with right fuel (no water) but just for very short periods because overheating would have been pretty much instant without water injection.

Another interesting piece of data is ETO kill claim part of the USAAF statistical digest. Before January 1944 US fighters did not claim so many kills but after that claims steadily rise. Turning point appears to be the Big Week and after that claims still increased and continued in the same level until September. Basicly early P-47 operations did not affect a lot to Luftwaffe, seems that it was combined pressure on all fronts during summer 1944 which broke back of the Luftwaffe.

gripen


Thanks for the links to the test reports, it is interesting reading. I seriously doubt that NACA abused these engines as severely as did combat pilots. Once engaged, most pilots pushed everything forward and never even glanced at temp gauges until the fight was over. Engine changes were extremely common, pilots came home with all manner of engine damage from burned valves, to melted sparkplug electrodes, to melted piston crowns. It's a wonder more didn't go down over France and Germany. One pilot in the 357th never accumulated more than 20 hours on an engine before he trashed it by overboosting for sustained periods. Finally, the extremely irritated Group C.O. ordered the pilot to assist in all engine changes. Suddenly, his engine (Merlin) ceased to be abused....  ;)

During early to mid 1943, only a handful of Fighter Groups were operating out of Britain. Towards the end of the year, the number of groups skyrocketed. In addition, the Luftwaffe generally ignored fighter sweeps. By early '44, there were enough long-range P-38s and P-51s that their effect began to take a much greater toll on the Luftwaffe. Still, the vast majority of fighters continued to be P-47s until mid 1944 when the P-51 began replacing the P-47s (not just supplementing them) in the 8th AF.

Here's a chart showing which groups flew what and when the deployed. Not that deployment does not mean operational. It usually took anywhere from 2 to 8 weeks before a new unit was declared operational. The yellow lines on the chart indicates the date when the squadron was released as operational.



My regards,

Widewing
« Last Edit: November 27, 2003, 11:53:09 AM by Widewing »
My regards,

Widewing

YGBSM. Retired Member of Aces High Trainer Corps, Past President of the DFC, retired from flying as Tredlite.

Offline HoHun

  • Gold Member
  • *****
  • Posts: 2182
Re: Re: Re: Re: Re: Re: Bob Johnson's observation of Luftwaffe fighters
« Reply #25 on: November 27, 2003, 01:14:09 PM »
Hi Widewing,

Before we lose sight of it:

>Then, how do you account for the P-47M-1-RE and P-47N-1-RE recording CORRECTED speeds of 475 and 467 mph respectively on 2,800 hp?

Where's you rspeed data from, and where's the evidence compressiblity correction has been applied to it?

Regards

Henning (HoHun)

Offline HoHun

  • Gold Member
  • *****
  • Posts: 2182
Bob Johnson's observation of Luftwaffe fighters
« Reply #26 on: November 27, 2003, 01:23:53 PM »
Hi Widewing,

>Once engaged, most pilots pushed everything forward and never even glanced at temp gauges until the fight was over.

Even with pushing everything forward, 72" Hg gives you no more than 300 extra HP (you only claimed 200 HP) over 64" Hg.

Starting from 2600 HP, that's around 10% of power gain, which yields around 3% of extra speed.

To get to 470 mph TAS, Johson's P-47 would have had to go at 456 mph TAS at standard power settings. And that below its optimum altitude, so the total top speed must have been even higher.

Where's your evidence for a 460+ mph top speed standard P-47D?

Regards,

Henning (HoHun)

Offline HoHun

  • Gold Member
  • *****
  • Posts: 2182
Bob Johnson's observation of Luftwaffe fighters
« Reply #27 on: November 27, 2003, 01:57:55 PM »
Hi Widewing,

>Still, the vast majority of fighters continued to be P-47s until mid 1944 when the P-51 began replacing the P-47s (not just supplementing them) in the 8th AF.

The total claims by 8th Air Force fighters amount to 7422.

This is the distribution of the claims over time:


12/1943:   6%
04/1944:  25%
08/1944:  54%
12/1944:  82%
05/1945: 100%


Referring to your chart, 75% of the Luftwaffe fighters claimed by the 8th Air Force were claimed in a period when the P-47 equipped less than 25% of the 8th Air Force's fighter groups.

Only 25% were claimed while the P-47 still equipped the majority of the fighter groups.

Regards,

Henning (HoHun)

Offline gripen

  • Silver Member
  • ****
  • Posts: 1914
Bob Johnson's observation of Luftwaffe fighters
« Reply #28 on: November 27, 2003, 04:45:41 PM »
Widewing,
Well, I'm quite sure that men at NACA did abuse R-2800 under tests, just read the report.

About deployment of the P-51 it should be noted that 352nd FG converted partially to P-51 in the beginning of the March and flew operationally, 355th converted fully in March and flew operationally. In addition 363rd FG of the 9th AF flew escort missions with the P-51 in March. In practice there were six FGs flying escort missions with P-51s at March, twice more than operational P-38 groups in ETO at that time and quite close number of P-47 groups.

HoHun,
You should note that 58" rating for the B-series R-2800 is 2300hp with water injection and 64" rating 2535hp with water. The dry rating at given MAP is lower because there is no charge cooling effect of the water injection, amount of this effect is normally couple %.

gripen

Offline Widewing

  • Plutonium Member
  • *******
  • Posts: 8801
Re: Re: Re: Re: Re: Re: Re: Bob Johnson's observation of Luftwaffe fighters
« Reply #29 on: November 27, 2003, 07:48:05 PM »
Quote
Originally posted by HoHun
Hi Widewing,

Before we lose sight of it:

>Then, how do you account for the P-47M-1-RE and P-47N-1-RE recording CORRECTED speeds of 475 and 467 mph respectively on 2,800 hp?

Where's you rspeed data from, and where's the evidence compressiblity correction has been applied to it?

Regards

Henning (HoHun)


Please, stop being obtuse.....

Virtually every source extent recognizes the USAAF published test data on the P-47M and P-47N. If you need actual data, see Dean's "America's Hundred thousand", pages 282 and 283.

My regards,

Widewing
My regards,

Widewing

YGBSM. Retired Member of Aces High Trainer Corps, Past President of the DFC, retired from flying as Tredlite.