Kelly Johnson’s Visionary Lockheed P-38 Lightning, It’s Role in Winning the War in the Pacific, and Its One Design Flaw That Never Got Fixed

Toward the end of World War II, while the P-51 Mustang was busy helping to win the air war over Europe, an entirely different high-altitude interceptor mastered the skies over the Pacific.  The P-38 was an innovative design for extreme speed and altitude that required a lot of bugs be wrung out of it before it became an effective weapon against the Japanese A6M “Zero.”

Compressibility effects that locked up control surfaces, engine failures and supercharger glitches caused the plane to be labeled “dangerous” after a large number of crashes when the plane was introduced to combat.  As described in the video, these all got fixed, and the plane was eventually credited by its pilots with winning the air war in the Pacific.

However, one glitch that never got fixed lived on to torment future aircraft designers, like Bob Pond with his Lightning-like “Pond Racer,” shown below.

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It was a subtle glitch and one that never caused any problems except in certain conditions that caused the plane to enter a “flat spin” condition.  The flat spin is a condition that terrifies all pilots because of the large number of them killed by it.  Normally, rudder control and throttle can be used to get out of a spin or to prevent it, and that works most of the time.  But some aircraft, especially those with very large “moments of inertia” around the vertical axis, like the P-38 and most “wide” or “squarish” planes, have a fatal tendency to stick like glue in a flat spin, resisting all efforts to get out of it.  Further, it’s hard to eject safely from an airplane in such a spin.  So, not a good thing.

Later aircraft of similar planforms, like the McDonnell Douglas F-15, solved this problem with very large vertical stabilizers (tail fins).  But the P-38 was designed at a time when speed was the absolute driving factor.  It needed to go 400 mph to beat the Japanese fighters, so it’s tails were made small and aerodynamic.  Even the Pond Racer did not really have adequate tail surface area to keep it out of spins, though with its three tails, it was better than the P-38.

Few pilots talk about the flat spin problem with the P-38, and it’s not mentioned in historical works, like the video above.  Having established itself as a heroic icon, the plane really doesn’t need to be criticized by its admirers.  Who, in his right mind, would criticize the slight wrinkles that Raquel Welch seems to have picked up now that she’s in her 70s?  No gentleman, certainly.  It would be absurd to criticize such an iconic beauty, who remains so, even to this day.

And I’d certainly be the last to criticize.  Yet, I do mention it, if only because it’s something to keep in mind for the future.  I wouldn’t even be aware of it except for the whispers of a P-38 pilot on a dusty runway near Petaluma, California back in the 1990s.  He’d taken up ultralight flying, for fun, in his last years, but he’s long since gone on to the clear skies of the next life.  He knew I was an aerospace engineer at Lockheed at the time, and he told me about the problem like he expected me to fix it in future models.  “Kelly made the vertical stabs too damn small.  I lost two buddies because of it.  Get on that.”  Heh.  I’m sure he’s already told Kelly Johnson himself since then.  But I’ll keep it in mind.

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About GruntOfMonteCristo

Fearless and Devout Catholic Christian First, Loving Husband and Father Second, Pissed-Off Patriot Third, Rocket Engineer Dork Last.
This entry was posted in 'Murica, Aircraft, Uncategorized, War, World. Bookmark the permalink.

26 Responses to Kelly Johnson’s Visionary Lockheed P-38 Lightning, It’s Role in Winning the War in the Pacific, and Its One Design Flaw That Never Got Fixed

  1. Papabear says:

    When I was a machine operator at Lockheed Calif. Co I happened to be running a Kearney and Trecker Bridge Mill when some “suit” came up on my platform to show his entourage what I was doing. Noticing that he wasn’t wearing safety glasses I unceremoniously told him to get off my machine and get behind the yellow line drawn around my machine. He dutifully got down, put on his safety glasses, came back up and resumed his little tour. About an hour and a half later my boss came to me and asked if I knew who it was that I threw off my machine. I said “I don’t CARE who it was, he wasn’t wearing safety glasses!” He said, “THAT was Kelly Johnson, and he LOVED it that you demanded he put on his glasses. THANKS! It made ME look good too!”

    • Chana says:

      Granted its not connected, I’ve always wanted to travel in a trainer like the astronauts do.

      and it’s been a long time since we built the T-38. Wonder if we could build (a little one) one that could make the 7000 mile trip from here to my hometown (drop-tanks are fine) traveling say mach 1.3 over the ocean / Mediterranean, with a guy, his wife, and two kids, and still be able to land on a carrier in an emergency. Engines have come a long way since then. (raptor has a 9 to one thrust to weight. I think back in the day 2 to 1 was good.)

    • THAT is a hell of a story, Papabear. You threw Kelly Johnson off your mill! AND you didn’t get fired for it! Up in Sunnyvale, where I worked, I knew guys who got fired for stuff like that. Kelly wasn’t your average suit; that’s for sure! Thanks for the story!

      • Papabear says:

        Sunnyvale was Lockheed Missiles, right? My father-in-law worked up there before I met my wife. They moved back to Simi Valley and he went back to the Burbank plant. We lived two blocks from one another for 6 years before we met.

        • Cool! Yes, Sunnyvale was Lockheed Missiles and Space. I was actually an airplane guy early on, but ended up going into space & launch vehicle stuff later. That’s how I ended up there. But the really cool stuff was always down south in the Antelope Valley at the Skunk Works and in Burbank, where you were.

          • Papabear says:

            My favorite job ever was working as a CNC machinist at a place called Rocketdyne, where we made the Shuttle Main Engines! What a RUSH! I made one combustion chamber for Columbia, and all three on Challenger, Discovery and Endeavor. Made various other components for the SSME plus ancillary parts for other cool things. Made parts for an 18″ green laser in 1977 when Jimmuh Cahtuh said we WEREN’T spending money on SDI. But the combustion chamber was my favorite. When I took it off my 4-axis CNC the last time it was worth $750,000.00. The SSME was small enough (without the nozzle) to fit into a short-bed pickup and developed 1,500,000 horsepower!

            • That’s something to be proud of. The SSMEs were precision rocket engines. Nothing, to my knowledge, has turbo-pumps that spin faster or develop more pressure than those things. Still, I admired those big Saturn V F-1s. A Sunnyvale engineer I worked with had spent time on the test stands at Marshall in Huntsville test firing those beasts. Made your insides shake bad.

            • Papabear says:

              I don’t have my spec sheets right here, I LIED… here they are. The Oxygen turbopump spins 70,000 rpm, and the hydrogen turbopump turns at 95,000rpm. Put THAT in your kim-chee and smoke it, kim dong il!

            • I thought they both spun at over 100,000rpm??? Is that maybe the 105% throttle numbers?

            • Papabear says:

              Well the spec sheet I have listed the RPM under the banner “nominal characteristics”, so I guess it could indicate the starting point of operation. On the Hydrogen side; Flow is 628gpm, discharge press psia is 4560, NPSH minimum is 1332 feet, developing 2543 bhp, inlet press psia 3420, inlet temp R=1876, press ratio 1443, and gas flow= 6.48, so this is quite an engineering marvel.

            • I’m impressed! And just off the top of your head! 😉

            • papabear1950 says:

              Of COURSE it was off the top of my head… not much hair to get in the way anymore.

      • Papabear says:

        Thinking about the plane stories, I got to sit in the cockpit of an F-104 when I was 5. I think that got my juices flowing for airplanes. Flew a Piper Cherokee, (NO, NOT Elizabeth Warren), for a little while once… way cool.

        • The 104 was a beautiful plane. I could never understand how it flew with that huge engine and those itty bitty wings. But it did. The image of riding Pocahontas makes me a little queasy. Not your fault, though. Nothing a little bourbon can’t fix!

  2. woodsterman says:

    WELL? Is it done yet?

  3. LL says:

    Flat spin problem (that I wasn’t aware of until this post) notwithstanding, I would have given my left nut to fly one in combat. However you had to be shorter than I am (under 5’8″) to fly the aircraft and that’s so unfair. Howard must have been catering to the vertically challenged.

    • A lot of fighters need a can opener to get even short guys in and out of the cockpit. And if you’re built the wrong way, with a long torso and short legs, it’s even worse. You can’t just drive with the canopy open.

  4. Jules Smith says:

    You had me at most lethal. You’ve given me the desire to fly in a super fast military plane, Top Gun. Like I haven’t got enough things to do….

    • It’ll happen, Jules. But it wasn’t me. You probably got the urge from your motorcycle ride a few days ago! Those road rockets are a blast. I wish I had one!

      • Papabear says:

        My best friend for years flew an F-15 in the Air Force. He told me he could go from 0 to 1,500 mph in under a minute, but I told him I’d beat him in the 1/4 mile. My bike would do 0-60 in the same time as a 2006 Bugatti Veyron.

  5. solaratov says:

    Another of the most beautiful – and most deadly – fighters…………..

    I love this plane.

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