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old man emu

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In a callous appraisal, Lindbergh's crossing of the Atlantic only required him to keep flying in an easterly direction and stay awake. Provided that his plane's engine was reliable, by doing those two things he'd would hit Europe somewhere and thereby complete the task. After succeeding at that, one would think that he spent the rest of his life living off the celebrity the flight created for him. But I know of two things that he did that had profound effects on the development of trans-oceanic flight.


In the year following his historic transatlantic flight to Paris, Charles Lindbergh, flying again in the Spirit of St. Louis, lost his way at night over the Gulf of Mexico, somewhere between Havana, Cuba, and the southwest coast of Florida. The problem started with his magnetic compass going haywire, losing him a steady heading. At that time maintaining a course over oceans relied on two things - a mariner's chronometer and a sextant. 


Mariners' chronometers had been available for a century or two, as recounted in Kenneth Slessor's poem:

Two chronometers the captain had,
One by Arnold that ran like mad,
One by Kendal in a walnut case,
Poor devoted creature with a hangdog face.

However these chronometers were not accurate enough for the speeds at which aeroplanes flew. Previous chronometers could be set only to the minute; this was an acceptable error for 19th century mariners who might go weeks or more before stopping and making an adjustment, but not for 20th century pilots who could use radio broadcasts to synchronize their timepieces. A watch error of 30 seconds could throw off a position calculation as much as seven miles.


That April 1927, Lindbergh went to observe air operations aboard the USS Langley, where he encountered an enthusiastic Navy Lieutenant Commander, Philip Van Horn Weems, who was conducting navigation experiments for carrier-based aircraft. Weems demonstrated several of his innovations to Lindbergh, including is prototype Second-Setting Watch: the first true aviator “hack” watch that could be set precisely to the second. (Later, the military realized a major benefit of this precision, and began to synchronize multiple watches for field operations, thus making famous the line “Gentleman, synchronize your watches.”)


Lindbergh petitioned the White House for Weems to be assigned as navigation tutor. Weems used most of the lessons to teach Lindbergh how to find his position by shooting the sun with a very rare sextant. It was a 1924 Bausch & Lomb model, of which only six were made, and Weems believed it was still the best model available in the United States. Bubble sextants had been around for more than a decade, but because so little attention had been paid to aerial navigation, their design had not advanced much. During his sessions with Lindbergh, Weems carefully studied the sextant’s deficiencies, later taking his notes to the National Bureau of Standards, which worked with Bausch & Lomb to produce an improved version that saw wide service in the 1930s.


Another Weems innovation used in Lindbergh’s training was the Star Altitude Curves, a revolutionary set of charts that let a navigator find his position using two stars (one was usually the North Star, Polaris). The graphs helped cut the calculation time from 15 minutes to 40 seconds.




And his second contribution?


During WWII, Lindbergh toured the South-West Pacific as a representative of the Vought company who built the Corsair. While there he showed the pilots how to lean out the mixture of their engines to obtain better fuel economy and range https://www.ozatwar.com/ozatwar/lindbergh.htm

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Yes, for the Americans. I believe that the Japanese Navy pilots had been taught to do that well before the Pacific war started. They also traded airspeed for endurance in long distance flights. Because the Americans had ample fuel supplies, they didn't seem to worry about using it, so would run full rich most of the time and at top cruise speed. 


I wonder if the escorting fighters in Europe leaned off and powered back to keep station with the bombers. Anyone got a P51 Pilots' Manual to check? 


Found it!  https://wiki.hoggitworld.com/images/8/83/North-American-P-51-Mustang-Pilot-Training-Manual.pdf


It seems that the P51 had some sort of automatic mixture control.




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6 hours ago, old man emu said:




...During WWII, Lindbergh toured the South-West Pacific as a representative of the Vought company who built the Corsair...

I’ve read that while there, he bent the rules, going on operational missions and becaming the only civilian to shoot down an enemy aircraft.

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43 minutes ago, old man emu said:

Yes, for the Americans. I believe that the Japanese Navy pilots had been taught to do that well before the Pacific war started. They also traded airspeed for endurance in long distance flights.?.


In his book Samarai Saburo Sakai often mentioned their pilots’ skill in leaning for long range flights. On one transfer flight in his Zero he circled Clarke Field until the engine ran out fuel-  after 12 hours and 5 minutes.

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21 minutes ago, Old Koreelah said:

In his book Samarai Saburo Saka

I'm sure that's where I read about the Japanese leaning the mixture and reducing power. 


As an aside, I think that managing performance by mixture control and power output are things that "hourly hire" kills. If you want to go from A to B and you are hiring the aircraft by the hour, then it's WOT to get to B before the Hobbs Meter empties your wallet. I suppose that you could calculate how using a lower power setting and leaned mixture could reduce the cost of the trip if you were dry hiring. It also calls for the wise use of wind to obtain the biggest tailwind vector you can.

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Over the years I have been flying there has been a big change in engine handling. Originally we were taught to leave mixture full rich below 5000' and never run over square, that is hundreds of rpm less than manifold pressure in inches.

Much to the irritation of all those who love the old wives tales, we now lean at just about any time except full power at take off below 5000'  and with constant speed props  it is safe to run well oversquare.

The annoying thing is that there are still a lot of people who tell us we are ruining our engines. Even the engine manufacturers don't agree with all that we do.

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