Friday, October 17, 2014

The Friday Flyby - October 2014

Before this tank killer came on the scene...
(U.S. Air Force photo by MSgt William Greer)

There was this beast...

Ju-87 Stuka Flight over Poland, 1939
Bundesarchiv Bild 183-1987-1210-502, Polen, Stukas by Hoffmann, Heinrich CC

Before we dig in here, just want to mention that yes, the Flyby is back. On a trial basis, so to speak. Right now I'm thinking of making it a monthly thing as opposed to weekly as it was in days of yore. (Hence the title reflects the month, rather than the date, as it did in olden times.) Now with that bit of "administrivia" out of the way, let's dig in!

The Ju-87 Stuka (which is a German abbreviation for Sturzkampfflugzeug, which is simply the German word for dive bomber) did not begin World War II as a tank buster. That came later in the war and only on the Russian front.


At the beginning of the war the Stuka was mainly responsible for close air support and was pretty effective at that job. As long as there weren't any enemy fighters in the neighborhood. For the Stuka was kind of slow and ungainly with those fixed landing gear and a top speed of only 242 mph. Though there was a rear gunner, he only had a single machine gun.

Not something to sneeze at, but not much use against a good man in a fighter.

The Stuka was very effective in both Poland and France in the early part of the war when the Luftwaffe had air superiority over the front. And that siren you hear so much about (well, you hear about it if you're a WWII buff, as I am) it was a real thing. The Germans mounted one on either landing gear strut, usually both. They called it the Jericho-Trompete, or Jericho trumpet. Like the horn that brought down the walls of Jericho in the Old Testament.

It was kind of eerie and rather demoralizing to men who have been pounded by German artillery, strafed and bombed, attacked by tanks and are generally on the run as their generals try to figure out this Blitzkrieg thing.


The Battle of Britain opened up with the Stukas going after shipping in the English Channel, heavily escorted by Me-109s as the Germans wanted the RAF Spitfires and Hurricanes to react to those shipping attacks in order to wear the RAF down.

Later, the Stukas went after the aerials of the Chain Home radar stations along the southeast coast with very little effect. Little effect on the radar aerials that is. The Stukas were shot to pieces by the nimble Spitfires and Hurricanes.

This clip from the film Battle of Britain shows this nicely. (Though the Stuka attack profile isn't "quite right" as they say. Since when does Hollywood ever get it right?)


It's my understanding that the film company actually had a flyable Stuka used sparingly during filming. So those scenes above used a lot of special effects. Those effects seem primitive now but I remember being impressed when I saw this movie in the theater back in the '70s. (Let me see, I think I went and saw that film six times. Have watched it many times since. It's not bad. Oh yeah, I loved Trevor Howard's portrayal of Air Vice Marshal Keith Park. He's in that clip.)

Here's the "proper" technique for "moving mud" with a Stuka -
Flying at 4,600 m (15,100 ft), the pilot located his target through a bombsight window in the cockpit floor. The pilot moved the dive lever to the rear, limiting the "throw" of the control column. The dive brakes were activated automatically, the pilot set the trim tabs, retarded his throttle and closed the coolant flaps. The aircraft then rolled 180°, automatically nosing the aircraft into a dive. Red tabs protruded from the upper surfaces of the wing as a visual indicator to the pilot that, in case of a g-induced black-out, the automatic dive recovery system would be activated. The Stuka dived at a 60-90° angle, holding a constant speed of 500–600 km/h (350-370 mph) due to dive-brake deployment, which increased the accuracy of the Ju 87's aim.
When the aircraft was reasonably close to the target, a light on the contact altimeter came on to indicate the bomb-release point, usually at a minimum height of 450 m (1,480 ft). The pilot released the bomb and initiated the automatic pull-out mechanism by depressing a knob on the control column. An elongated U-shaped crutch located under the fuselage swung the bomb out of the way of the propeller, and the aircraft automatically began a 6 g pullout. Once the nose was above the horizon, dive brakes were retracted, the throttle was opened, and the propeller was set to climb. The pilot regained control and resumed normal flight. The coolant flaps had to be reopened quickly to prevent overheating. The automatic pull-out was not liked by all pilots. Helmut Mahlke later said that he and his unit disconnected the system because it allowed the enemy to predict the Ju 87s recovery pattern and height, making it easier for ground defences to hit an aircraft.
Physical stress on the crew was severe. Human beings subjected to more than 5 g forces in a seated position will suffer vision impairment in the form of a grey veil known to Stuka pilots as "seeing stars". They lose vision while remaining conscious; after five seconds, they black out. The Ju 87 pilots experienced the visual impairments most during "pull-up" from a dive.
Eric "Winkle" Brown RN, a British test pilot and Commanding Officer of Captured Enemy Aircraft Flight section, tested the Ju 87 at RAE Farnborough. He said of the Stuka, "I had flown a lot of dive-bombers and it’s the only one that you can dive truly vertically. Sometimes with the dive-bombers...maximum dive is usually in the order of 60 degrees.. When flying the Stuka, because it’s all automatic, you are really flying vertically... The Stuka was in a class of its own." Wikipedia
Stuka dive attack
(Ju87V2 by Aleksej fon Grozni Public Domain)

In 1943 in the East, the ever increasing numbers of Soviet tanks required an answer, the Stuka returned to combat in it's G variant sporting a couple of 37mm cannon. It was known as the Kanonenvogel, the "cannon bird."

Ju-87G Kanonenvogel of Schlachtgeschwader 2
(Bundesarchiv Bild 101I-655-5976-04, Russland, Sturzkampfbomber Junkers Ju 87 G by Grosse CC)

Probably the most famous Stuka pilot was Hans-Ulrich Rudel. There was a bit of a kerfuffle regarding this man recently due to his input being sought on the design of the A-10. It was much ado about nothing. The man was an expert ground attack pilot, you do solicit the opinions of experts when designing something. Of course, there are certain types who will wet their knickers at the thought of asking a former Nazi for anything.

From whom do you think we learned a great deal about rocketry? It wasn't the Boy Scouts. You do what you gotta do sometimes. As Rudel died back in 1982, seems fishy that the anti-A-10ites bring that up now.

Anyway, Oberst Rudel knew his business and practised it very well indeed.

Hans-Ulrich Rudel
Oberst, Deutsches Luftwaffe
(Via Wikipedia - http://en.wikipedia.org/wiki/File:HansUlrichRudel.jpeg)

Hans-Ulrich Rudel (2 July 1916 – 18 December 1982) was a Stuka dive-bomber pilot during World War II. The most highly decorated German serviceman of the war, Rudel was one of only 27 military men to be awarded the Knight's Cross of the Iron Cross with Oak Leaves, Swords and Diamonds, and the only person to be awarded the Knight's Cross of the Iron Cross with Golden Oak Leaves, Swords and Diamonds (Ritterkreuz des Eisernen Kreuzes mit goldenem Eichenlaub, Schwertern und Brillanten), Germany's highest military decoration at the time.

Rudel flew 2,530 combat missions claiming a total of 2,000 targets destroyed; including 800 vehicles, 519 tanks, 150 artillery pieces, 70 landing craft, nine aircraft, four armored trains, several bridges, a destroyer, two cruisers, and the Soviet battleship Marat. Wikipedia
I had a model of the Stuka when I was a kid. 1/24 scale by Airfix. It was a big model, I'm surprised it survived as long as it did. But I had it for a long time. I'm sure it's still somewhere in The Olde Vermonter's attic. Or was. I do wonder what happened to that bird?

Chase this link to see a beautiful rendition of this model. Lots of great photos.
Needless to say, mine was not this nice, nor this detailed!

So there you have it, another Old AF Sarge favorite. (I know, I know. I have so many favorites, but hey, if it flies...)

"Junkers Ju 87B-2 Stuka" by Kaboldy - Own work.
Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons CC

35 comments:

  1. Wahooo! It's back! Friday's are special again. With Movies and Tanks getting blown up!

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    1. I knew you'd like the tanks blowing up.

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    2. I think there's something a little fishy with the wikipedia numbers. Starting a pullout from a 90 degree dive at ~1500' at 350k with 6 g's seems pretty low to me, frag pattern of the weapon notwithstanding. When I get home, I'll try and find my old dive charts and see what they say.

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    3. Ah, expert testimony. Whatever you find, let me know. I'll fix that!

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    4. Googled "aircraft dive recovery charts", and came up with one from the Navy for A-7s. Entered the chart at 1500' so 350k indicated is close enough to 350k true, dropped down to the 90 degree dive line then moved over to the 6 g line and came up with ~4000' of altitude needed to recover. The A-7 would be able to maintain 6 g better in the dive, but that's offset by the stuka getting slower and therefore tightening up it's turn radius. Would really need an aero engineer to say yay or nay, but I'm leaning toward Nay. Also, there's that little matter of a bomb going off in the vicinity.

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    5. It's not in your part of the post, it's in the quote from Wikipedia. I think it's wrong there.

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    6. I agree juvat. I don't think there's any way you could induce that pig to hit 350-370 mph. I'm not sure that with a bomb load it could make 220 mph, which would be about 350 kph. And with the dive brakes out I'm guessing less than 200 mph, perhaps closer to 150 mph, even in a near-vertical dive.

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    7. I need to do some more digging. Most of the data I've seen online for the Stuka seems to match what's in Wikipedia. The source cited in Wikipedia for that data is a World War II Luftwaffe source, which does not seem to be available online. Leastwise not with a rather cursory search.

      The dive speed may or may not be correct. Even with the dive brakes extended though, gravity still gets a vote. Then again, the figures Juvat cites (who is after all a pilot and has "been there done that") seems to indicate that the pull-out altitude seems pretty low.

      I'll have to see if I can find my copy of Stuka Pilot and see if Rudel himself addresses this topic.

      Damn, you guys have really piqued my interest in WWII dive bombing!

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    8. Just re-reading part of Rudel's book. He doesn't mention a lot of technical data. The one time I see him mentioning speed in a dive he did note seeing 375 on the clock while disorientated in a dive through clouds. He pulled at 1200 feet by altimeter and hit the trees, though he recovered and returned to the airfield. His pull out could have been much lower than 1200 feet due to altimeter lag and there's no mention of the target elevation so who knows. The a/c was a writeoff. At a slight tangent, some of the SBD drivers at Midway reportedly pressed to 800 feet and recovered very close to the water but without any great drama. You're right about gravity but there's also terminal velocity to consider, that speed at which neither gravity nor thrust can overcome aerodynamic drag.

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    9. I should be out fixin' fence this morning! Instead I'm giving in to my craving for guilty pleasures.

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    10. Yeah, c'mon PA, those fences ain't going to fix themselves!

      Glad you checked out Rudel's book, now I don't need to. OTOH, Fringe (see comment below) gave me some German technical references to peruse later on.

      We shall see. (Or perhaps I should say wir werden sehen...)

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    11. Despite my skylarking about on the internet I still got a lot of fence repaired. If I could read German I'd have been in serious trouble today.
      https://drive.google.com/file/d/0B02W0Rs5-hblQkZHV0ZyaXR0UWM/view?usp=sharing

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  2. "Since when does Hollywood ever get it right?" Hollywood seldom cares if it's right, they just care if it looks good!! (Even if sometimes it's to the point of being ridiculous!)
    Welcome back Friday Flyby!! Even if it's once a month it'll be great. I always learn something from your research. Example: "the propeller was set to climb" - I didn't know that they used variable pitch propellers that far back.
    Great blog!!

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    1. Sometimes I'm happy if it looks good (as long as we don't slide into ridiculous!) For me, Battle of Britain was an excellent film and though it's not 100% correct, it looks good. In fact, it looks damn good.

      (Did you know they wanted partly cloudy days so that the flying sequences would have the clouds in the background, which heightens the sense of motion?)

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  3. Yay! Flyby! My day is beyond any risk of being ruined now!

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    1. Heh. The day is still young. Lots of time for Murphy and Belle to get in trouble!

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  4. Now I have something to read gain on Fridays! Still have something to look at- like Fishnet Friday, but reading is good too.

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    1. Glad you liked it. No War Hoovers but still it's all good.

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  5. Spekenzie deutch?

    http://www.avialogs.com/index.php/en/aircraft/germany/junkers/ju87stuka.html

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    1. Ja, natürlich!

      FWIW, you made my day!

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    2. Check your PMs on FB. Might be able to extend the joy.

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  6. Very well done, Chris. I had a Stuka model as a child, too. There was one helluva air battle goin' on on the ceiling of my bedroom when I was 13... think Testor's glue and thread.

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    1. Same here. Had Huns mixing it up with Messerschmidts, World War I birds in formation with WWII birds.

      I know the look!

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    2. That's Huns as in F-100s. Re-reading my comment I noted that one could get confused. At least I did.

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  7. Fascinating post. Thanks so much for sharing.

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  8. Scroll down to the second statement by Gen Hozzel and in that statement he says norm was 700m and lowest was 500m.

    http://www.allworldwars.com/Conversations-with-a-Stuka-Pilot-Paul-Werner-Hozzel.html

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    1. Yeah, that sounds more reasonable. ~250-275K and ~2100 feet with an "absolute" minimum release of ~1500. I bet it was still exciting as 500KG bombs (third section of his remarks) AKA 1100Lb bombs would have a frag pattern that would have to be contended with. And with the g of the pullout, the stuka would slow down very quickly, leaving it in that pattern for a longer period of time. Would take some brass ones to do this day after day.

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    2. Great stuff Marc, especially that website.

      The bird slowing down very quickly probably cost a lot of Stuka crews their lives. Poor bastards didn't have much chance with enemy fighters to begin with.

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  9. Just as an FYI.
    Corner velocity is defined as the velocity (airspeed) at which you can turn the smallest turn with the fastest turn radius and meant your were pulling max g available for that airspeed. For an AT-38, corner velocity was 350k at 6g (which was what wikipedia said was the parameters for a Stuka). That diameter was 6000' or a radius of 3000'. 6 g and 350K is a constant, so it doesn't matter if it's an At-38 or a Wright Flyer, if your pulling 6 g at 350 k (or a Stuka), your turn radius is 3000'. Which meant, if you pickled at 350k at 1200', your aircraft was going to impact slightly long of the target, but was not going to fly away. Physics is an important subject and is one of those immutable laws of nature.

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    1. I need to find more material like this. The discussion it sparked has been priceless. I'm glad we have a number of aircrew in the audience. (Not to mention having two of you "on staff" as it were.)

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  10. Looking at the pix at the top called to mind a post of Buck's that referenced the fact that 100% of 20th Air Force were casualties. I wonder how many of the Stuka pilots survived the war. An excellent post.

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    1. That's an interesting question. I may need to chase that down.

      Thanks Cap'n.

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Just be polite... that's all I ask. (For Buck)