... the original arrival date was March 20, 1937, three and a half months earlier than the actual arrival date and the runways had to be completed by that earlier date.

I think that Earhart could be pretty confident that the airport would be waiting for her.

The idea I floated that she may have been anxious on the state of the airfield is based on these TIGHAR reported facts. Is it arguable that she may have been anxious about this brand new airfield? Yes. But how many of you **pilots out there would take off for a mid ocean airfield** just constructed at your request that no one had ever landed on and you know nothing about?? **And it's near the end of your normal fuel load and no nearby airports as alternates?** Is it **LIKELY she was anxious? ** True or false?

I remember flying across the Atlantic in a single engine airplane looking for the mid ocean airfield on Santa Maria Island when the thought ran through my head, "Kid, you are taking it on faith that the guy that drew this chart wasn't just playing a practical joke and that the island is really where it is plotted on the chart." Then, just as quickly, I realized that the chart was drawn by grown-ups who took their responsibilities seriously, knowing that peoples' lives depended on the care they took in doing their work and "that was that," that first thought never crossed my mind again. And the island was there, just where it was supposed to be.

Earhart also knew that grown-ups were in charge of building the airport on Howland so I don't see any reason for her to have had any anxieties on that score.

gl

Btw If you look at Gary's takeoff calculations below you see that a runway of 2250, 2550 or even 2700 is cutting it mighty fine if she is using the east west runway. The one with the prevailing winds. If she had the same info as Gary then wouldn't AE be "anxious" about that airfield? The same woman who ground looped a fully loaded Electra in Hawaii on a runway with "known" conditions?

"What Johnson said was correct for a 14,000 pound takeoff without flaps but was definitely NOT TRUE for a 15,000 pound takeoff which takes significantly more than 2,000 feet at standard conditions and even more at the 2,000 foot density altitude at Lae. According to report 487, it takes 2,600 feet to take off without flaps at 16,500 pounds at a sea level density altitude. Doing the same calculations we did before, we find that a takeoff at Lae at a density altitude of 2,000 feet and 15,000 pounds without flaps results in a ground run of 2,278 feet. Lest you think that this is all just theoretical mumbo-jumbo, this calculation agrees quite closely with Chatter's observation of 2,550 feet, a difference of only 272 feet, less than a 12% difference thus Chatter's observation confirms the accuracy of this calculation. (I accept Chatter's report as more accurate in all of it's detail compared to Collopy's short letter.)

It is interesting to look at what would have happened if Earhart had completely filled that tank, adding about 50 U.S. gallons weighing 300 pounds. A takeoff at 15,300 pounds without flaps would have taken 2,370 feet, only 92 feet longer. And if she had put the flaps down to the 30° position specified in report 487 the takeoff would have taken

**only 1,914 feet providing a 1,086 foot safety margin, 57% extra runway.**We know that Earhart did not fill that tank because she believed that she needed 100 octane fuel to get maximum power out of her engines but Pratt and Whitney documents show that the engines make full takeoff power of 600 horsepower using the 87 octane fuel available at Lae (Jeff Neville disputes this) so she could have filled that tank, made a safe takeoff, and then have an extra hour of flying endurance to find a safe place to land.

Just for the sake of argument, let's say that Neville is correct and that she could only get 550 horsepower from each engine using 87 octane fuel, how would this have affected the takeoff? The length of the takeoff run varies with the inverse of the ratio of the engine power. Report 487 shows 2,100 feet for standard conditions, 30° of flaps, and 16,500 pounds using the full power of 600 horsepower from each engine, a total of 1,200 horsepower so taking off with a total of 1,100 hp gives a takeoff distance 9% longer, 2,290 feet. We adjust this for the takeoff weight of 15,300 pounds as we did before and find 1,970 feet. We then increase this by 6% to account for the density altitude so the complete calculation gives 2,088 feet compared to 1,914 for 1,200 hp (we could have just multiplied the 1,914 by 1.09 too), only 174 feet longer and with 912 foot safety margin, 44% extra runway available. Doing the same calculation for the flaps up scenario produces a takeoff run of 2,585 but this would be cutting it close so Earhart would have to have remembered to set the flaps correctly.

So no matter how you figure it, Earhart unnecessarily left behind an hour's worth of fuel and this fuel could have made a significant difference in the end. ".

From the thread In Aircraft and power plant, Octane Analysis, reply 44. I'm not sure which runway he is suggesting she is using but the one I highlighted at the top adds up to a 3000 foot length and the closest to that is the reported 2900 foot runway. See runway lengths in

http://tighar.org/smf/index.php?action=dlattach;topic=528.0;attach=431 supplied by Gary in Octane analysis. Did I get my facts wrong here or is there a math problem?

Not being a pilot means I am ignorant of certain facts so I trust people like Gary to set me straight. I apologize in advance if I'm getting something wrong here or being seemingly misleading.