Sunday, June 10, 2018

F4H-1 WINGTIPS

Ok, I have been working on my new (version 15) master drawings for the F-4 Phantom.  I have chosen to start from the beginning with the F4H-1. When I do master drawings, I do a lot of research, looking at pictures, and so forth. I lay out a grid with the Fuselage Stations, the Butt lines, and the Water lines.  I begin by gathering all the measurements I can, station number references, and any other information that will put a particular part at a particular location.  I then start by laying out the "skeleton" of the aircraft, locating as many ribs and spars as I can (this usually gives a good reference to where panels and joints occur.  In fact, I probably spend just as much (or even more) time researching and looking for answers as physically drawing.  I try to make everything as accurate as possible.

This week I have been working on a new bottom view, and so far I have been working on the wings.  One thing I have noticed is the different wingtip variations.  According to NAVWEPS 01-245FDA-3-1, there appear to be two different options here (in reality three).



1. The first is found on 142259 through 148374 unless they were modified with ASC (Aircraft Service Change) 40 and 41. Here is my illustration of this variation:


You can see in this drawing that first of all, it has an inset leading edge light. Next, the trailing edge light is smaller and recessed.  Information in NAVWEPS 01-245FDA-3-1 seems to support this.  Finding photographic evidence is much harder.  I think I see it, but most pictures are taken from so far away that when you blow it up to get better detail, well, you just can't be sure.


Here is a picture of 145313 (the 14th airframe) with the original wingtip.  See how clean and devoid of bumps, humps, and lumps.  This is actually a fairly good picture of the original wingtip.


Here is a picture of 148254 (the 26th airframe) still sporting the old wingtip. Not as nice a picture, but it clearly shows a very clean wingtip.


This is a picture of 148261 (the 33rd airframe) with what seems to be the original wingtip.



2. The second variation was installed on 148375 through 15102 and any aircraft that had ASC 40 and 41 take place. Here is my illustration of this variation:


This version has the more traditional trailing edge light.  NAVWEPS 01-245FDA-3-1 indicates that these aircraft still had the early leading edge light.


This is a picture of 146820 (22nd airframe) with what seems to be the mod with still the old style leading edge light.  See what I mean by pictures not showing very much detail?

One of the things that make this change odd, is that it took place mid-block, rather than starting a whole new block with the change.  148375 was the 13th aircraft in block 6, there were 9 more to be constructed in that block.



3. The third variation is what eventually became the production version. OK, now the 1 million dollar question.  When was the "bug eye" leading edge light introduced?  I don't have the foggiest.  I see pictures of the F4H-1 airframes later in life with the "whole package" of newer wingtip lights.


The "bug eye" leading edge nav light clearly would have better side visibility.  Don't know if this was the only reason for the change.  But you can see pictures of it scattered throughout the F4H-1s, most often later in their careers.



This picture of 145307 (first Block 2 aircraft, the 8th airframe) shows later in life it had the production wingtip retrofit.



Here is a picture of 148265 (the 37th airframe) with the "full monty."

Of course, this post probably brings up more questions than it answers.  If you have any answers, I would love to hear from you so this change can be fully documented.




Revision History:
  • 09 JUN 2018 - Original Post
Sources:
  • Artwork by Kim Simmelink
  • NAVWEPS 01-245FDA-3-1
  • Pictures from the internet