Jump to content

F-111 astrocompass


Recommended Posts

So can someone educate me on the astrocompass located on some of the F-111s, especially the EF-111. I've been going over pictures in different books and Internet and I'm finding some have, and some dont. I'm starting to guess that the EF-111s that had it must have been jets that were converted from other jets that had them. Hope someone can help me as I'm getting a headache because of this.

 

Duane 

Link to post
Share on other sites

I'm sure to be corrected, but I think only the FB-111A had the astrocompass. It was removed when they were converted to the G models.

There were however some EF-111s, and I believe F-111Fs that incorporated GPS late in their career, utilizing a big antenna in front of the windscreen where the astrocompass was on he FBs.

Edited by Hoops
Link to post
Share on other sites

what Hoops says.

 

The astrocompass was a flush glass sensor fitted to a bulged FB glare shield.

The GPS antenna, fitted as part of the digital updates circa 1991-1993, was more of an upturned dinner plate in the same spot.

 

Tony

Link to post
Share on other sites

Nope, it was an upgrade program started I think during or before Desert Storm as the only gray painted F-111E had it, then as per usual McDonnell/Boeing bucks come into play and made the armchairs can it

 

Luigi

Link to post
Share on other sites

No FB-111As were rebuilt as EF-111As.  All EF-111As were converted from F-111As.  The conversion was done by Grumman, not by GD or USAF.  

 

All production FB-111As were originally built as FBs.  The prototype for the FB was 83-9783, the 18th (and last) pre-production F-111A.

 

in 1990 30 FB-111As  were modified and redesignated as F-111G when they were transferred from SAC to TAC.  Those not reassigned to TAC were sold to Australia (RAAF) to supplement their F-111Cs.

 

(edit: expanded for completeness)

Edited by habu2
Link to post
Share on other sites
On 8/14/2018 at 2:46 AM, Falcon053 said:

So can someone educate me on the astrocompass located on some of the F-111s, especially the EF-111. I've been going over pictures in different books and Internet and I'm finding some have, and some dont. I'm starting to guess that the EF-111s that had it must have been jets that were converted from other jets that had them. Hope someone can help me as I'm getting a headache because of this.

 

Duane 

 

The Astrocompass was only fitted to the FB-111A, it was removed when they were converted into the F-111G. It was a small  hump aft of the radome and forward of the cockpit glass above the avionics bay...

 

Im not sure what you are talking about when you say some have it and some dont... Maybe we are thinking about different things. If you show me what you are talking about maybe i can tell you what it is and what jets had it.

Edited by ElectroSoldier
Link to post
Share on other sites

Here is a link to a Cannon EF-111...

 

https://commons.m.wikimedia.org/wiki/File:430th_Electronic_Combat_Squadron_-_General_Dynamics_EF-111A_Raven_(EF-31)_67-037_with_Cannon-based_F-16_524th_TFS.jpg

 

So were the EFs that had them a GPS that looked like an astrocompass? I haven't seen any Mt. Home Ravens or Upper Hyford have them.

Link to post
Share on other sites

I've seen pics of EFs with a circular GPS shape ahead of the windscreen but they don't have the raised area like the FB astrotracker had.  The EF GPS looks like a plate as previously mentioned.

Link to post
Share on other sites
10 hours ago, Falcon053 said:

Here is a link to a Cannon EF-111...

 

https://commons.m.wikimedia.org/wiki/File:430th_Electronic_Combat_Squadron_-_General_Dynamics_EF-111A_Raven_(EF-31)_67-037_with_Cannon-based_F-16_524th_TFS.jpg

 

So were the EFs that had them a GPS that looked like an astrocompass? I haven't seen any Mt. Home Ravens or Upper Hyford have them.

 

That's the GPS Antenna, which is flat on the panel and larger. The Astrotracker was housed a prominent bulge with the smaller glass window that was exclusive to the FB-111A

Link to post
Share on other sites
10 hours ago, Falcon053 said:

Here is a link to a Cannon EF-111...

 

https://commons.m.wikimedia.org/wiki/File:430th_Electronic_Combat_Squadron_-_General_Dynamics_EF-111A_Raven_(EF-31)_67-037_with_Cannon-based_F-16_524th_TFS.jpg

 

So were the EFs that had them a GPS that looked like an astrocompass? I haven't seen any Mt. Home Ravens or Upper Hyford have them.

 

Yes the Astrocompass and the GPS dome antenna were fitted into the same place.

AMP was multi stage, the GPS was if not one of then it was thee last stage. All the jets had transferred to Canon from Upper Heyford and Mountain Home by the time the GPS dome was added. You can even find picturesd of CC marked jets without the dome.

 

For modelling purposes no MO or UH jet should have the GPS dome fitted to it.

Link to post
Share on other sites
5 hours ago, ElectroSoldier said:

 

For modelling purposes no MO or UH jet should have the GPS dome fitted to it.

 

F-111E 68-050 was the gunship grey jet at RAF Upper Heyford with the GPS mod in 1991. I saw it up close in 1992 and it had been repainted in the SEA night scheme. UH tailcode, red fin top for 77th FS.

 

Tony 

Link to post
Share on other sites
3 hours ago, tony.t said:

 

F-111E 68-050 was the gunship grey jet at RAF Upper Heyford with the GPS mod in 1991. I saw it up close in 1992 and it had been repainted in the SEA night scheme. UH tailcode, red fin top for 77th FS.

 

Tony 

 

Yeah he was talking about the EF-111A.
If he had asked about a different jet he would have got a different answer.

 

Im not sure what the SEA night scheme is...

I know 68-050 was the only UH AMP jet to have gunship grey painted over the whole plane even between the ventral strakes, after 68-050 that area was left black because of the oil film they had to try and clean off before painting took to much time.

Link to post
Share on other sites
3 hours ago, IAGeezer said:

Anyone have some good pics and/or dimensions of the Astrotracker? I'm trying to scratch one for my 48th Academy FB.

I dont sorry, the FB-111A wasnt a common visitor to any UK air base so I never really got any photos of any of them. They were even shy at RAF Mildenhall.

Link to post
Share on other sites
5 hours ago, IAGeezer said:

Anyone have some good pics and/or dimensions of the Astrotracker? I'm trying to scratch one for my 48th Academy FB.

 

I had a great shot of the FB-111A  nose, looking down, which was used in a couple of books.

Will have a look on the PC this weekend and see if I can find it.

If you want to search, it was the Litton AN/ASQ-119 astro compass.

 

HTH

 

Tony 

 

Link to post
Share on other sites

I promise to look this w/e. The shot(s) I have show the geometry very well, if the publishers sent them back or they were digitized. Failing that, I will dig up my ancient Aardvark books.

 

Tony 

Link to post
Share on other sites

Why don't you guys try searching for images of RAAF F-111G's instead?

 

The astro compass was removed but the fairing it sat within remained. It was a raised rectangular section in plan view which blended into the curved upper fuselage section forward of the windscreen.

 

There were ex USAF FB-111A/F-111Gs that served with the RAAF before their eventual scrapping, although at least two airframes survived disposal

Link to post
Share on other sites
On 8/17/2018 at 7:20 PM, tony.t said:

I promise to look this w/e. The shot(s) I have show the geometry very well, if the publishers sent them back or they were digitized. Failing that, I will dig up my ancient Aardvark books.

 

Tony 

 Does the T. stand for Thornborough? I have your 1993 Osprey F-111 book, and it is terrific! I continue to be amazed by the talent on these forums!

Mstor - thanks for the pics... I really need to go back to the SAC museum. Soon.

Link to post
Share on other sites

Yes, one and the same. Thanks for the kind words. There's a nicely preserved FB at Ashland. I'll continue looking for the relevant shot as it shows part of the astrocompass gizmo under the glareshield porthole.

 

Cheers

 

Tony 

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...