What may have happened aboard Earhart’s Electra that last morning…
(The following re-telling of Amelia Earhart’s final flight from Lae to Howland on July 2, 1937 is based on research and findings by the Waitt Institute Flight Reconstruction Team. It is a best approximation as to what happened aboard the Electra that fateful day.)11
Lae, New Guinea
Early in the morning on July 2, 1937, Amelia Earhart and Fred Noonan awoke and prepared for their departure from the small grass runway strip at Lae, New Guinea. After receiving some maintenance and a pre‐flight check, Earhart’s Electra was deemed ready for its longest, most challenging flight segment of the entire World Flight.
Weather forecasts were manageable and looked good for most of the route, though the westbound headwinds would reduce their ground speed and lengthen their time in the air. At Howland Island, their final destination, the Coast Guard cutter Itasca was stationed with men and equipment ready to assist in maintaining, refueling and sending the Electra on its next leg to Hawaii.
The Final Flight Begins
At 10 a.m. local time (0:00 GMT), Earhart and Noonan barreled down the runway in a heavy Electra. The fuel quantity on board was sufficient for the planned 18‐hour flight, plus four hours of extra fuel—Earhart’s typical safety margin. Once airborne, Earhart observed the forecasted thunderstorms roughly 300 miles east that likely impeded a direct flight path along the coast of New Britain, and across northwestern Bougainville Island.
Earhart set a heading approximately 20 degrees right of the direct track to Howland, flying east to Choiseul island, immediately south of Bougainville, to avoid the dangerous weather further north. At Choiseul Island, she turned back to the northeast with a plan to rejoin the direct track from Lae to Howland at Nukumanu Island, which would provide an excellent and visible checkpoint for their location.
After making a radio call to report their position near Nukumanu Island, Earhart must have noticed the sun setting behind them. They were flying in good weather, and were aware that the headwinds were blowing at 23 knots, or 26.5 mph, only slightly greater than predicted. This wasn’t a concern, as they knew that forecasts for the second half of their flight called for a reduction in these headwinds.
Electra Misses USS Ontario
Up ahead, the Navy’s USS Ontario was positioned along Earhart’s direct track as a guide to check their location and progress. However, at just 185 feet in the length, the Ontario was probably too small to sight and lacked the ability to communicate via radio with Earhart. She overflew it, possibly never seeing it.
Shortly afterwards, Earhart did see a ship’s lights, reporting via radio, “… a ship in sight ahead…” It was the merchant steamer SS Myrtlebank, en‐route to Nauru Island from New Zealand. In the vicinity of the SS Myrtlebank, just south of Nauru Island, Earhart also reported seeing the lights on Nauru Island that she expected to visually acquire. These lights must have been easily visible in the dark, night ocean and told Earhart that they were making their expected progress toward Howland.
The moonless night and good weather, with reduced and steady winds, afforded Noonan an excellent evening of smooth flying and celestial navigation. In the darkness outside his navigator’s window, Noonan could employ 11 of the 57 brightest stars in the night sky and four of the best planets to fix his position and progress across the Pacific. These were tasks Noonan knew well, as one of America’s most experienced and competent air navigators in 1937.
Howland 200 Miles Away
After 17 hours and 45 minutes of flight, Noonan’s navigation fixed their position at 200 nautical miles from Howland Island, a calculation that was likely accurate to within as little as four nautical miles. The flight appeared to be nearly perfect at this point, and it nearly was, except for a likely failure of a very important instrument used in setting engine power levels for minimum fuel consumption, called the Cambridge Fuel Analyzer. This instrument was necessary to gain maximum range for their fuel load, and without it, fuel consumption would increase.
The Electra’s Cambridge Fuel Analyzer had been problematic since their stop in Miami nearly a month earlier, and had suffered significant failures, multiple times, in the 10 days before leaving Lae. But it had been repaired in Lae and upon departure, likely functioned without any problem.
Fuel Analyzer Failure
This failure possibly occurred in the time between 0418 GMT and 0900 GMT, at four to nine hours into the flight, where a return to Lae would have taken almost as much time as continuing to Howland. At this point, Earhart likely concluded that the risk of landing at Lae’s unlit field on a moonless night was far higher than the risk of continuing in good weather to Howland, at slightly increased fuel consumption, and arriving just after sunrise.
A decision to continue to Howland with the inoperative Cambridge Fuel Analyzer would have to be managed as best they could. That would mean an unavoidable, nearly 48% reduction in fuel reserves upon reaching Howland’s vicinity. Earhart and Noonan would have just 90 minutes to locate the island, rather than the four hours planned in her safety margin.
Critical Navigational Error
An additional adverse factor arose as Earhart approached Howland from her position 200 miles west. From either a navigation calculation error, or a poor estimate, Earhart reported about 100 miles out from Howland, when she was actually 146 nautical miles west of the island. The implications were critical—Earhart commenced her descent approximately 40 nautical miles further west than she had planned, arriving to the sight of an empty Pacific Ocean.
When Earhart and Noonan needed their best effort, it may have unintentionally fallen short. Research concludes that after 16 hours awake, human performance severely degrades and judgment and is significantly impaired. Both Noonan and Earhart had been awake for nearly 24 hours. Noonan was up early getting time checks of his chronometers, and Earhart had flown a 30‐minute test flight at 6:30 a.m. that morning.
Search for Howland
At 1912 GMT, Earhart believed she had reached where Howland should be. With no land in sight, she commenced a confined area search near the arrival point. Seeing nothing west or east, she circled for a few minutes to clear her mind, and set about a systematic plan to search for Howland and Itasca.
Where is Howland Island?
Sixteen minutes later, Earhart headed north on their sun Line of Position, a course line running between 337 and 157 degrees determined from Noonan’s sight‐reading at sunrise. Forty‐five minutes later, she reported that she was on that course line and likely flew back and forth on it at maximum endurance speed in a search pattern looking for Howland Island, Baker Island, or the Itasca.
After searching for 61 minutes, Earhart had used nearly two‐thirds of her entire fuel reserve, which was critically low. She had made several radio reports and was having trouble communicating with the Itasca. Despite her best efforts, she could not get a bearing on the Itasca’s position via her Bendix radio direction finder. Itasca was also unable to obtain a bearing on Earhart, mostly due to radio transmission times less than what was needed to complete this process.
She made her last call at 2013 GMT – “We are on the Line of Position 157‐337, will repeat this message on 6210 KCS. Wait listening on 6210 KCS… We are running north and south.”
While continuing to search for a sign of Howland, Earhart’s tanks ran dry between 2013 GMT and 2100 GMT. The left engine likely quit first–it powered the only generator on the aircraft–and the radios required this generator to transmit and receive. On a single engine, the Electra could maintain flight, but fuel exhaustion for the right engine was now only minutes away. Earhart would soon have to ditch the aircraft, hoping she and Noonan would survive the landing and be rescued before nightfall.