Navigating the LOP with the offset method.

[h.a.c. van asten]

R.G. Agreed . I somewhere have read that , when "gingerly inching down" , Earhart was by the navigator advised to keep the radio (bearing) station slightly to the right when being 80 mls off . Will try to find back.

[Ted G Campbell]

"gingerly inching down" - pay attention!  What did Kelly recommend as an approach power setting?  I've pointed this out to you before.
Ted Campbell

[h.a.c. van asten]

TG.Cmpbll . The report "Inching down" etc. is from Earhart herself in one of her books written before July 1937.

[h.a.c. van asten]

TdG.Cmpbll .  If all your RDF exercitions went awry when on a direct to target course , so that you do not know where exactly you are. Question : how would it then be possible to announce "We must be on you ..." at a defined  point of time ?  The answer is that besides RDF you have another fashion of fixing your course tracks.

[Ric Gillespie]

Question : how would it then be possible to announce "We must be on you ..." at a defined  point of time ?  The answer is that besides RDF you have another fashion of fixing your course tracks.

You're hoisted with your own petard. We know that the RDF aspect of the flight did not work so if Noonan used an offset there was never a time when he (or AE) could say "We must be on you..."

[h.a.c. van asten]

R.G. If you steer on your offset circuit @ 1815 GMT (sunrise o/b was @ 175453 , @ 1815 supposedly 100 mls out , alt.1,000) , the offset lane being 102 mls , you reach the Turn Off Point on the position line @ 1859 GMT , then 30 mls offset to go course 157T and you arrive @ the Howland (assumed) coordinates at 1912 GMT , A/c´s groundspeed 139-140 mph.

[h.a.c. van asten]

TdG.Cmpbll . "gingerly inching down". The C.Johnson report mentioning "power glide @ 100-150 mls off" is of June 19 , 1936 , hence it concerns the "1st" attempt with at the end of the flight the vast (´main´) land of New Guinea , with no risk to miss it when being off course.

[h.a.c. van asten]

MkPetsn. For a navigator like Noonan it was child´s play , when on any land point , to establish their latitude of position by the sun at noon and the sun a few hours later. It was even possible to measure the longitude (by the s.c. Douwes Formula) , or by a two-star fix. Why then , transmit useless bundles of words " received" by "Betty" in lieu of the coordinates they were close to , or the island they were at ?

[Ted G Campbell]

Boy are you way off in your understanding of Kelly's data and aircraft operational specifications!  If you think Kelly drew up op specs based upon where AE was going to land you have no idea of what an aircraft goes through to be certificated.

Stick to your navigation mumbo jumbo and stay away for aircraft performance.

Ted Campbell

[h.a.c. van asten]

TdG.Cmpbll . Sounds not very scientifically . I btw for the purpose studied Aircraft Performance Theory at Delft , The Netherlands , U.O.T. , Aeronautical  Faculty , 1988-2004.

[h.a.c. van asten]

T,Cmpbll . 1815 to 1912 GMT is 57 minutes. !815 " 100 mls out"  radio . For straight in approach A/c should have made 105 mph (this being considerably below "Johnson") , or , A/c should have arrived at 1840 for "Johnson" , lower limit . The difference of 32 min to 1912 represents an any length detour   D = X - 100  within reasonable speed limits of A/c.

[Ted G Campbell]

What?
Ted Campbell

[Chris Owens]

[... post deleted by author in an attempt to elevate the overall tone ...]

[Patrick Dickson]

for Alan...

That, my friend, is a Classic post ! Thank you for stating so eloquently what we've all been thinking.
Well done, sir !

pd

[Dan Swift]

"What's our vector Victor?"   "We have clearance Clarence!"  "Roger.....huh?"  "Roger, over.....What?"   "Roger...huh?"