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Amelia Earhart PNG Theory

Old 4th May 2018, 18:31
  #341 (permalink)  
 
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David you talk about commercial operations and delivering "as fast as possible". Attemting to discredit what is fact for min fuel calculations. This is wrong. My experience internationally is,almost without exception ,flight plans were based on min cost. Cost index is inputed, Location (price) of fueluplift and tankering are all considered.Optimun Levels speeding up in a head win will increase fuel consumption but is part of the algorithum of min cost. For 10 years our plans listed direct operating costs. Routing was considered and the plan that cost less was the top option.
Erhart was heavy. Military ops in, admittedly British piston AC after WW2, with a miltary load out of Cairo for south would be dodging sandhills 30 miles from Cairo
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Old 4th May 2018, 22:15
  #342 (permalink)  
 
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So Greg, you're saying that she wouldn't have got the range that David has suggested because she was more concerned about the cost of fuel, time and aircraft and wanted to get there quickly? So, rather than conserve fuel, she flogged it there thinking that they would definitely find Howland and not be concerned about enough contingency fuel?

Personally I don't think she would have flogged it any harder than the dead horse that you are still flogging right now.
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Old 5th May 2018, 15:42
  #343 (permalink)  
 
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Is there any reported data on prior legs' distance/duration/fuel uptake, to establish some sort of SOP for the crew?

Human psychology being what it is, advancing the throttle to "get through it" is common. Been there myself and dealt with "well under fuel minimums" after subsequent diversion.
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Old 5th May 2018, 17:56
  #344 (permalink)  
 
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I think the whole thread is a bit like flogging a dead horse but if anyone believes the long distance flights of the '20's and '30's weren't watching their fuel like a hawk they are crazy

These weren't commercial or near commercial - they were EXPLORATION - worse than even test flying.. Even now people flying small aircraft over long oceanic crossings are fuel crazy - read any article by a delivery pilot.....

I suspect that they were so focused on range and endurance (which they could monitor) that the risks of course (which they had little precise info on by modern standards), came a bad second
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Old 5th May 2018, 23:45
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A couple of replies:

Originally Posted by AbsoluteFokker View Post
Is there any reported data on prior legs' distance/duration/fuel uptake, to establish some sort of SOP for the crew?

Human psychology being what it is, advancing the throttle to "get through it" is common. Been there myself and dealt with "well under fuel minimums" after subsequent diversion.
i'll take a break from the plot for a while to reply to this by Absolute Fokker.

Researchers do not know much about fuel uplifts after a Long Distance flight but there is the one example and that was after the March 1937 SFO-Hawaii flight 2400 miles to Wheeler AFB up the valley from HNL.

The SFO Fuel load was 947 USG and at about the 14 Hour point of the 15:51 total for the flight, it was realised that they would arrive at Wheeler in the dark (they at one stage had a G/S of 180 mph), so the power was reduced from cruise power to an IAS of 120 mph and Earhart wrote, "We are burning less than 20 gallons of gas at 10,000 feet" (Ref: Page 36/37 of "Last Flight" written from her notes). At that fourteen hour point the Lockheed published fuel usage for a Long Distance flight should have been 713 USG, leaving 234 USG. Now, "some people" say that the 20 USGPH she said she was using was "40 USGPH" because the fuel flow gauge was a twin needle instrument BUT this is denied by the fact that Earhart reduced power from the normal cruise fuel usage of 38 USGPH at that stage of the flight, so how can a reduced power setting use more than 38 USG. ? Personally, from my workings with the low AUW's and the low power required it is possible to get the fuel flow down into the "Low 20's on an endurance flight". So slowing the Electra down presumably started the descent process, i.e: My opinion is that what Earhart was saying was that a power glide was started at that point and the power she had selected at 10,000 feet produced that Fuel Flow reading, that to me is the more likely scenario but it is in the book in B & W..... That opinion is confounded, however, because in the book Earhart says, "80 miles from MAKAPU (the beacon) Fred says start down"...... There were nearly two hours (before their arrival at Wheeler) ....at the aforesaid 14 hour point.....of a low power slow descent on the approach into OAHU which was by rounding Diamond Head passing HNL and heading up the valley for Wheeler. My workings show that with 458.3 square feet of wing area the Electra was a bit of a floater at low AUW's only needing low power to keep going.

Earhart told the assembled Press that she had "over four hours of fuel left to search for OAHU if they had missed it".

They landed at Wheeler and the Civilian Fuel Contractor started putting fuel in. He was stopped by Paul Mantz who discovered contamination in the chamois leather fuel filling funnels they were using and the refueling was stopped. How much did they put in before it was stopped ? We don't know, but it could not be to the required load for HOWLAND which was 900 USG for the 1900 Statute Miles Hawaii-Howland because they needed more fuel.....

Next, it was decided to fly the Eectra to LUKE Field on Ford Island as the Army would sell them High Octane fuel there. Paul Mantz then flew his fiancee around OAHU sightseeing for about a half hour on the fuel that was in the Electra and landed at LUKE Field where the Army refuelled the Electra up to 900 USG by adding 590 USG. So when the Electra landed at LUKE, there must have been 310 USG in it after Mantz's fly-by using probably 40 USG at low level meaning 350 USG in the Electra on departing Wheeler Field and if the contractor added 50 USG at the most before he was stopped then the Electra landed at Wheeler after the Long Range flight from SFO with 300 USG which is about the "Over 4 Hours" that Earhart quoted that she had left of Low-level Fuel usage at say, 60 USGPH..

If that is the conclusion then it is obvious that the Electra used "less" fuel than the Lockheed figures which are 100 USGPH for 1 Hour, 60 USGPH for three hours, 51 USGPH for three hours, 42 USGPH for three hours, and 38 USGPH for the rest.

For Harry of Heathrow:

Who says: "I suspect that they were so focused on range and endurance (which they could monitor) that the risks of course (which they had little precise info on by modern standards), came a bad second".

I guess any pilot who is given a wind forecast of 12-15 mph would be a bit disconcerted at finding a wind of 26.5 mph at 7 Hours into a LR Flight. Fuel assets would be of very high concern at that stage with easily over 11 1/2 more hours to run on the original FP.. Far from what was supposed to be an average G/S of 138 Mph my workings show an average of 130 mph at that 7 Hour point but it gets worse when they turn full on into the wind at NUKUMANU and between NUK and the U.S.S. ONTARIO (427 SM over 3.6 Hours) the average G/S drops to 119 mph.. Fuel would indeed be a major concern and could explain why Harry Balfour in LAE heard "On course for Howland at 12,000 feet" saving a little fuel by going higher....?

Back to the plot, still a long way to go.

Last edited by David Billings; 15th May 2018 at 01:38.
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Old 6th May 2018, 01:59
  #346 (permalink)  
 
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Of course there was no concern for cost. To fly furthest with least fuel used is LRC not staying in air longest which is holding or endurance . David is attempting to discredit min fuel with his post about commercial ops and getting people to b fastest which is untrue.
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Old 6th May 2018, 02:57
  #347 (permalink)  
 
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Question

[QUOTE=David Billings;10139059 . . . .

Back to the plot, still a long way to go. . . .[/QUOTE]

Did you get my PM of may 2 -- ?
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Old 6th May 2018, 06:28
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Greg 47

David is not trying to "discredit" anyone. David is trying to find out by working an Excel plot of the flight if it was feasible to get back to ENB.

You are entitled to your opinion as I am entitled to mine.

The Factual side of the Project says that there is a wreck there which is unidentified with evidence to say that it had Wasp engines and that it is the Electra.... that should get any aviation person's interest.

The Hypothesis side attempts to explain how that factual evidence could be true. You seem to think that I am saying a Hypothesis is automatically correct... that is not so, a Hypothesis is designed to draw discussion which is exactly what it is meant to do and is doing.

You use the Lockheed fuel consumption figures to say the Electra used 900 USG by the time of 1912 GMT, I say the Earhart did not use those fuel consumption settings as far as I can see, particularly in the flight up to 1030GMT and that is borne out by the plot so far made to that 1030 GMT point.

The Plot has "what we do know" up to the 1030GMT point in regard to locations distances and timings. The Radio call at 0518 GMT with a Lat/Long of 7 d 3' South and the misheard "150.7" E (which should be "157.0’ E) say they were at least 120 miles south of the direct track to Howland so they did two doglegs, one through CHOISEUL and one at NUKUMANU. They had to see Nukumanu before night fell for a pinpoint PR, because it is “dead on” the direct track LAE-HOW.

Therefore, through these points, the distance from LAE by the time 1030GMT "Ship in sight call" and allowing a further 6 minutes for them to be overhead the ship at 1036GMT says they covered 1357 Statute miles because, for one other thing, the USS ONTARIO was "off-station" and making revolutions because of the surface wind and the ships log shows it to be 27 miles east of its designated station.

So, 1357 miles in 10.6 Hours says the average G/S was 128 mph (Which is 111 Knots, exactly what the U.S. Navy also made it) and the Lockheed power settings were not used. Every time I have used the Lockheed fuel consumption figures I have overshot the target distances, ergo, they were not used. Every time I have used the P&W Max Continuous for the S3H1, I have overshot the target distances also, ergo, that was not used either.

It is also plainly obvious that by climbing to 7000 feet initially and then climbing to 10000 feet sometime around 0318 GMT and then calling that she was descending at 0500 GMT that she was not following the Lockheed climb steps which limited 10,000 feet until “Hour 10” so if she was not following these she was following power settings that “she felt” were right at the time. So far, with the power settings in Horsepower, that I am using which are lower that the Lockheed settings, I am on time and on locations and I also cannot be on these locations unless I "wind-up" the wind. Remember the ONTARIO was experiencing 20 mph at S.L. so what would the wind be at 10,000 feet if it was also 26.5 mph Easterly at 8,000 feet ?. Also bear in kind that HOWLAND recorded 31 mph at 7000 feet on the morning of her expected arrival.

The plot has to have an increasing wind to make it work, that I will tell you. They surely should have known the wind was increasing when they reached CHOISEUL. The distance of 686 Sm done in 5.3 hours says a G/S of 129 mph. If she was using power settings to give a G/S of 138 mph average and was only getting 129 G/S average in a forecast of 12 mph what does that make the actual wind ? You tell me ....... Over the distance of 427 miles from 0700 to the ONTARIO at 1036 GMT she was only getting an average G/S of 119, do you have an idea of what the wind was ?

To the 0700 GMT Radio call point “Making 150”, I believe this was a Turnpoint and at 0700 GMT they saw Nukumanu off to their right which also is an alert that the drift caused (24 miles) was the result of an even stronger wind which Earhart confirmed as 23 Knots (26.5 mph) in her 0718 GMT Tx..

.
CONSO


Originally Posted by CONSO View Post
Did you get my PM of may 2 -- ?
Yes, I did and thank you. At the moment I have enough on my plate communicating with PPRuNe… ! Maybe later when I have finished the plot.

Last edited by David Billings; 6th May 2018 at 07:00.
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Old 6th May 2018, 10:00
  #349 (permalink)  
 
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David, your posts get more and more interesting. I wonder if your website material, and some of the other items you have posted on here ,could get published as maybe a low - cost digital book along the lines that a
few others in this Earhart search saga have done in the USA - where the big market and maybe a sponsor are to be found. Perhaps one of these specialist publishers in the US would find it sufficiently interesting to
fund it. .
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Old 7th May 2018, 01:33
  #350 (permalink)  
 
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The only thing i agree with is there is a good possibly of a wreck in ENB. She was 50% overloaded .The heaviest fuel load she had ever carried. Optimum would be possibly 4000ft. (Kellys figure some 2000lbs lighter) By climbing above optimum she wasted fuel. Why say "i must be on you". Howland was wrongly plotted and was some 6 miles in error. DR from the running fix could have a probable error up to 45 or so miles. Noonan was Pan-Ams premier pioneer navigator . Pan-Am pioneered pre war world wide remote navigation. It was common for ships to record the noon position local . This was the equivalent of a man on the moon for its day . The navy had positioned two or 3 ships? . Don't you think they would have looked in ENB . She was desperate to succeed . Going the other way she effectively had two more hours of daylight and would not have missed PNG. The navy had positioned fuel ,constructed 3 strips at Howland. Arriving early morning into the rising sun with minimum fuel was folly
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Old 7th May 2018, 03:25
  #351 (permalink)  
 
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Mainly for Greg 47 and also containing Items of Interest

I am pleased to read that in the least you agree that “there is a good possibility of a wreck in ENB” although you did not define or purport an opinion as to what it may be.

The first attempt at a RTW Flight also ignored the stepped climbs as it is apparent that Earhart ended up at 10,000 feet well before the scheduled 10 hour point of the Lockheed Fuel Plan.

The 2nd RTW flight positive fix at NUKUMANU was hardly going to be a [email protected] beam to Howland with some 1700 miles to run and the ONTARIO fix with 1272 miles to run would at the extreme only provide a then (for the time) standard 10% error of 127 mile either side of HOWLAND so the flight totally depended on Astro and the Radio TX of 1415 GMT was the first mention of “cloudy and overcast” meaning that any Astro obtained before that time was the last “fix” within a 10 miles “Circle of Position” and we do not know when Noonan took his Astro shots. It is said he was in the habit of shooting stars only once every two to three hours which would not be what I would want.

Our NAV on a GANDER to LAJES flight “at night” was shooting at any and every opportunity he could get with the Radar painting ice rings all over the place and St. Elmo’s Fire dancing around the windscreens. The weather was not nice. Why we were scheduled at night over the Atlantic in 1969, I have no idea, at least the engines were RR…..

So, if Fred missed a shoot during the period 1030 GMT to 1415 GMT and didn’t confirm his ten mile CoP between those times his last shot if at say, 1400 GMT, would lead him to DED-Reckon over some 870 miles giving him an 87 mile possible error either side of HOW. As soon as he goes into DED-Reckoning he would want the speed to be as stable as possible for accuracy purposes but without Astro he will not know the wind or the drift…. A terrible situation.

The U.S. Navy positioned three ships. ONTARIO was only the most useful one for the LAE-HOW run but turned out to be the least capable of assisting the flight and as I said earlier was out of position. The “Officially” required position was 3* 05’ S, 165* 00” E. What the ONTARIO Log shows is the 1000 GMT and the 1100 GMT positions with the ship running at 1.2 Knots and taking the “half” way point results in 2* 59’ 3.12” S and 165* 23’ 11.76” E (From the CD that is with the book “Finding Amelia” by Richard E. Gillespie of TIGHAR)[Data compiled by R Jacobson], therefore the ONTARIO was “North and East" of its’ Official position by 27 Statute Miles.

Incidentally the wind at S.L. that was messing with the ONTARIO was 20 KNOTS not mph so the correct value was 23 mph. At NUK it was 26.5 mph at 8000 feet as per Earhart’s Tx and I have to wind-it up into the low 30’s to get the distances and time to fit the sector NUK-ONTARIO at 12,000 or at 10,000 feet. I am not going to say at this stage the exact value I found on this example of the Excel Plot. It is also of interest that the USCG SWAN positioned halfway between Hawaii and HOW was also suffering from the wind and at one stage “lost” position and had to do a racetrack manoeuvre to get back “on station”, that can be seen from the Log. We also have the example of weird weather in the area by the USN PBY which suffered from icing at low-level and had to turnback for Hawaii.

Do I think they would have looked on ENB in 1937 ? How are, or is, “anybody” going to look on ENB ? From overhead in an aircraft ? Yes, if they get there in a reasonable time and not months after. The jungle swallows just about anything of aircraft size except a 747. Look how many “modern” aircraft are missing in PNG, including around the Rabaul area. I had a lead on General Walker’s B-17E aircraft “The San Antonio Rose” a few years back but can’t do anything about it. Even “more modern” white painted aircraft are difficult to find…. The Talair Bandierante that went missing 20 years ago has not been found as far as I know.

You say, “She was desperate to succeed…” yes, the intention was to get to Burbank by 4th July. One explanation is if she did increase the power and make a G/S of 150 mph.... because the 1300 miles ONTARIO-HOW would be done in 8.6 hours and 10.6 GMT + 8.6 hours = 1912 GMT, the time of the “Must be in you call”…. Provisionally, from the Excel Plot that will still leave some 300+ USG at HOW.

Harry from Heathrow expressed it succinctly…. The flight was “Exploration

Regards,
David

Last edited by David Billings; 8th May 2018 at 01:56.
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Old 7th May 2018, 06:55
  #352 (permalink)  
 
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Noonan surely had a sun shot of the rising sun approaching Howland. Regarding navigation Noonan was as good as it got.
If the US of A believed she could possibly be in ENB they would be there with their technology, like a shot. Winds over the north Atlantic are subject to frontal weather and are considerably different than equatorial where the lack of Coriolis means winds tend to flow across the isobars and there are no cold fronts. Tropical winds at altitude rarely exceed 20 kts and are prevailing. POM(PNG) is a good example in the s easter the Laurababa can be blowing 30-40 kts at sea level but a whisper above.
I said before that if the report was accurate as reported, then it deserves investigation. Who, no one knows yet. But Earhart and the Lockheed most likely are in very deep, i understand ,water around Howland.
Paul Allen is using a submersible to dive the war ship around Gizo (Solomon islands)that lost the 5 American brothers. He photographed recently, was it the Lexington ?,a casualty of the Battle of the Coral sea .
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Old 8th May 2018, 05:16
  #353 (permalink)  
 
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The Lexington and 60 aircraft deployed were involved in looking for Erhart. Inbound to HNL, on the first attempt, she slowed to about 90kts because of a strong tailwind .20 galls per hour would be what was expected . Thats a figure in the vicinity of best L/D or endurance.
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Old 8th May 2018, 23:42
  #354 (permalink)  
 
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Great reading yet again.

David when is the next perfect window for the next exploration if you can raise the $?
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Old 9th May 2018, 00:55
  #355 (permalink)  
 
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@ Global Aviator...

Seasons or climate have changed up there since we first went in in 1994. Then it was May to end September.

Now, it is July to mid-October. August is now stated to be the driest month. The local people do say there has been a shift in the weather. We went last June and we did get a large amount of rain, the first night was a welcoming downpour and an electrical storm which lit up the insides of the tent (and me !) for a good three hours, relieved when it was over.

David
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Old 9th May 2018, 04:27
  #356 (permalink)  
 
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David

I agree with Global Aviator (and so many others). I applaud your work, your diligence -- and your patience with those who fnd it difficult to read the available material.

Check your PMs.

Grizzled
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Old 12th May 2018, 08:58
  #357 (permalink)  
 
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Robert Gross letter

David, it would be interesting for readers of your website to see the Robert Gross letter to Putnam that you showed on here if
you could add that in the website somewhere..
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Old 12th May 2018, 21:27
  #358 (permalink)  
 
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@propertee64

I only have "a transcript copy of the original letter which had been notarised" for author Dick Strippel. This was sent to me by Bill Prymak a very well-known Earhart researcher of Denver, Co.. Whether that would be good enough for some people I have no idea. Which brings me to 'range' again...

Delving into the Range.

My recent (and ongoing) delving into the range of the Electra “again”, says it could get back to ENB under certain conditions, the start of those conditionds has to be in meeting all the requirements of the flight up to the 1030 GMT "Ship in sight" call but from there of course everything is an "unknown" except for the cloudy and overcast calls. not being able to get a ”null” on the DF and that she was down at 1000 feet for an hour and also that she was down to a half hour of gas but then comes back on the air after an hour !

What if they just kind of plodded on the way they had been doing but now are heading into a wind which was twice the upper forecast figure of 15 in the 12-15 forecast from Pearl Harbour ?. We know NAURU was reporting a 24 mph wind and Earhart herself said “23 knots” at 8,000 feet and we also know the ONTARIO was receiving 20 Knots from the East. TIGHAR has it that Howland reported 31 mph at 7000 feet on the morning of 2 July (Western Hemi.)

At the ONTARIO, shortly after the 1030 GMT call ( I consider that time to be 1036 GMT, 6 minutes and 12 miles later after the 1030 GMT call) did Noonan take an Astro shot or did he accept the Official US Navy position for the ship or did he get the position within a 10 mile “Circle of Position” ?

Why did they report in at 12,000 feet at 0800 GMT, did they go above cloud layers to avoid turbulence ?

All these things are variables which make it difficult to pin down where they were, particularly at 1912 GMT. Think about “Must be on you but cannot see you.” Must be on you for sure ? Must be on you by now ? We must be there by now ? It is a message of hope.

What do we know of the requirements on getting near to Howland ?

Seeing the sunrise and timing the flash of the sun on rising would tell them how far they were from Howland but if the sky is obscured where they are they will not see that and let us say they needed to be, say, 140 miles from Howland by 1736 GMT, because the sun rose at Howland at 1745 GMT. That would give them time to find on unobscured altitude from which they could see the sunrise and time it for the number of seconds before 1745 GMT.

From the ONTARIO at "my" 1036 GMT; by my working they need need to cover 1132 miles in 7.0 hours which means an average G/S of 162 mph into a headwind which I have in my workings of 32 mph at 10,000 feet and that will require a TAS of 194 mph using 60 USG per hour when Mr. Lockheed is saying they should be using 38 USGPH by that time in the flight.

There is then also a method of “Offset” before reaching Howland but if they don’t know where they are on the trackline, how will that work ? There is the DF which we already know Earhart was asking for on 7500 Kcs but could not get a direction although she did hear the letter A’s .

What do I get as a results ?

Well I get several results. The flight on the MS Excel plot from Take-off to 1030 GMT complies with times, distances, heights, radio calls and locations. It takes hours to work through the MS Excel columns of 100 lbs of gas usage and work the climbs into the flight. I used Cruise Climbs throughout.

Some combinations of height and speed result in splashdowns but I can get them back under certain conditions. For instance, it has to be leaving the ONTARIO at 155 mph TAS at 10,000 feet and at 1912 GMT they are 200 miles from Howland and they can get back to ENB if they climb back up again to 10,000 feet at 140 mph and then 150 mph for the rest. Of course, the wind has to be a tailwind. It takes 32.5 hours. Full details later. I am still working combinations of height and speed. I have not explored higher altitudes than 10,000 for a return but there is a slight fuel saving going higher.

Regards,
David

Last edited by David Billings; 13th May 2018 at 13:09.
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Old 12th May 2018, 22:30
  #359 (permalink)  
 
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[QUOTE
. ,. . t. Of course, the wind has to be a tailwind. It takes 32.5 hours. Full details later. I am still working combinations of height and speed. I have not explored higher altitudes than 10,000 for a return but there is a slight fuel saving going higher.

Regards,
David[/QUOTE]

Once again I suggest using excel solver to get matches and limits and combinations that fit known points .. especially if you have columns of data and some known intermediate ' end or fixed ' points re time, distance, altitude.

Last edited by CONSO; 12th May 2018 at 22:33. Reason: remove extraneous to suggestion
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Old 13th May 2018, 04:04
  #360 (permalink)  
 
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Excel Solver...

Originally Posted by CONSO View Post
[QUOTE
. ,. .
Once again I suggest using excel solver to get matches and limits and combinations that fit known points .. especially if you have columns of data and some known intermediate ' end or fixed ' points re time, distance, altitude.
CONSO... Thanks...

If you say it can solve a knotty problem like this then I'll look at it but right now I have other stuff to do (4 Bookcases for my wife's books) and I have spent over two weeks on this already. I have always been impressed by MS Excel and if the add-on will work on this I'll try it because doing it the way I have been doing it is painstaking in the extreme and at one stage with all the numbers I thought I was going blind ! A case of MEGO times ten ....

David
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