The KH-7 and KH-8 GAMBIT reconnaissance satellites

[Blackstar]

Something that I recently acquired is the performance reports for several of the last GAMBIT missions. That includes the camera operations--when they turned on and off both cameras (9 inch and 5 inch). There were a LOT of camera operations. Way too many to count, but it was in the thousands (my guessing here, but maybe 15,000+). The reports also cover all the systems and how they worked, when they started to get wobbly, etc. I could write way more than anybody would want to read about a few of these last missions.

I'm also hoping to talk to some of the people who worked on GAMBIT's camera system. We have good info on the people who worked on the CORONA and the HEXAGON. We have very little information on the people who worked on GAMBIT.

[hoku]

One interesting design aspect, which I hadn't appreciated previously, is the requirement to keep the GAMBIT camera in a constant thermal environment to ensure stable optical alignment (and hence consistently sharp images). Satellites in LEO transition every 45 min from direct sunlight into Earth's shadow and back. Larger space observatories like Hubble, or the telescope used for Roman/WFIRST in its original mission, would use heaters to keep the telescope at a constant temperature.

As explained by John H. Shafer, GAMBIT employed a dewar (thermos) design, with the camera optics installed in a polished Invar housing, surrounded by the spacecraft shell of polished Aluminium. The polished surfaces act as radiation shields.
https://forum.nasaspaceflight.com/index.php?topic=28180.msg2338391#msg2338391

This design also explains the nickname "silver bullet" Kodak engineers had for the GAMBIT 1 camera, as can be seen in the exhibit at Strasenburgh Planetarium in Rochester.
https://rmsc.org/science-museum/exhibits/item/712-gambit-satellite-optical-system

I wonder what level of thermal stability they could achieve with this "passive" design (with the primary heat input being the radiation from Earth entering through the camera aperture)?

[Blackstar]

Something that I have seen contradictory information about is the success of the first four GAMBIT (KH-7) missions. I think I have seen one document that indicated that "not one useable photograph" was obtained during those missions, but other reports that indicated that they worked, just not perfectly. I think that the problems may have been thermal rather than mechanical. The cameras operated, but the focus was a bit off because they had not yet solved the thermal control issues.

[hoku]

Something that I have seen contradictory information about is the success of the first four GAMBIT (KH-7) missions. I think I have seen one document that indicated that "not one useable photograph" was obtained during those missions, but other reports that indicated that they worked, just not perfectly. I think that the problems may have been thermal rather than mechanical. The cameras operated, but the focus was a bit off because they had not yet solved the thermal control issues.

Ah, now I understand your remark about the thermal control sections for GAMBIT in your post on the Kodak mystery collection: https://forum.nasaspaceflight.com/index.php?topic=15459.msg2198159#msg2198159

For MOL they considered a similar pattern of heater strips. This conflicts, however, with John Shafer's statement on the dewar design with the polished radiation shields.

[edzieba]

John's presentation runs from 00:38:08, and has lots of interesting details in particular on the G and G3 cameras. I didn't yet have a chance to check if his recent book "Gambit, Gambit Cubed & Dorian: Optical Metrology and Process Development at Kodak" has any more details on E-6.

An interesting mention near the end of the talk: Gambit 3's extremely thin film (the 1mil ESTAR base, described as 'saran wrap') was stretched as part of it's film transport, but most interestingly was coated in-orbit after exposure. Now my hands-on experience with Analog photography is all well after its heyday, but as far as I am aware post-exposure coating was only really a thing for some earlier Polarioid large format peelapart and pack films (not the integral instant films that survive today).

But the presence of the chemical handling and film application hardware inside Gambit is also an extra piece of the FROG puzzle: it indicates that the handling for the development chemistry would have been closer to a modification/duplication of an existing system rather than creation of an entirely new system.

[Blackstar]

An interesting mention near the end of the talk: Gambit 3's extremely thin film (the 1mil ESTAR base, described as 'saran wrap') was stretched as part of it's film transport, but most interestingly was coated in-orbit after exposure. Now my hands-on experience with Analog photography is all well after its heyday, but as far as I am aware post-exposure coating was only really a thing for some earlier Polarioid large format peelapart and pack films (not the integral instant films that survive today).

But the presence of the chemical handling and film application hardware inside Gambit is also an extra piece of the FROG puzzle: it indicates that the handling for the development chemistry would have been closer to a modification/duplication of an existing system rather than creation of an entirely new system.

This is really fascinating stuff. Thanks for bringing it to our (my) attention. Making film thinner so that they could carry more of it was a concern right from the beginning.

I am trying to turn my attention to GAMBIT, and I'm hoping to talk to some of the GAMBIT engineers. Although there is a ton of information available on GAMBIT, I have long found that simply interviewing a few people who worked on the hardware can be really illuminating. They can often answer "why" questions that arise from the histories and the documents.

[Blackstar]

An interesting mention near the end of the talk: Gambit 3's extremely thin film (the 1mil ESTAR base, described as 'saran wrap') was stretched as part of it's film transport, but most interestingly was coated in-orbit after exposure. Now my hands-on experience with Analog photography is all well after its heyday, but as far as I am aware post-exposure coating was only really a thing for some earlier Polarioid large format peelapart and pack films (not the integral instant films that survive today).

But the presence of the chemical handling and film application hardware inside Gambit is also an extra piece of the FROG puzzle: it indicates that the handling for the development chemistry would have been closer to a modification/duplication of an existing system rather than creation of an entirely new system.

I am going to start looking through documents, but was this previously revealed in the declassified documents? I'll have to look at "The Gambit Story." There is also a 1977 document prepared by EK describing the GAMBIT spacecraft. I wonder if it is in there. (When I locate that, I'll attach it to this thread.)

It would be kinda interesting if that fact was deleted from the declassified documents. But maybe it is buried in there.

[edzieba]

An interesting mention near the end of the talk: Gambit 3's extremely thin film (the 1mil ESTAR base, described as 'saran wrap') was stretched as part of it's film transport, but most interestingly was coated in-orbit after exposure. Now my hands-on experience with Analog photography is all well after its heyday, but as far as I am aware post-exposure coating was only really a thing for some earlier Polarioid large format peelapart and pack films (not the integral instant films that survive today).

But the presence of the chemical handling and film application hardware inside Gambit is also an extra piece of the FROG puzzle: it indicates that the handling for the development chemistry would have been closer to a modification/duplication of an existing system rather than creation of an entirely new system.

I am going to start looking through documents, but was this previously revealed in the declassified documents? I'll have to look at "The Gambit Story." There is also a 1977 document prepared by EK describing the GAMBIT spacecraft. I wonder if it is in there. (When I locate that, I'll attach it to this thread.)

It would be kinda interesting if that fact was deleted from the declassified documents. But maybe it is buried in there.

I had a look through the Gambit Handbook (https://www.nro.gov/Freedom-of-Information-Act-FOIA/Declassified-Records/Selected-Historically-Significant-Documents-of-Public-Interest/grsh/), but no mention of a coater or even a redacted space where description of one could be. The handbook only appears to cover G and not G*/G³ though, which is where the ultra thin base film would have come into play.

[hoku]

John's presentation runs from 00:38:08, and has lots of interesting details in particular on the G and G3 cameras. I didn't yet have a chance to check if his recent book "Gambit, Gambit Cubed & Dorian: Optical Metrology and Process Development at Kodak" has any more details on E-6.

An interesting mention near the end of the talk: Gambit 3's extremely thin film (the 1mil ESTAR base, described as 'saran wrap') was stretched as part of it's film transport, but most interestingly was coated in-orbit after exposure. Now my hands-on experience with Analog photography is all well after its heyday, but as far as I am aware post-exposure coating was only really a thing for some earlier Polarioid large format peelapart and pack films (not the integral instant films that survive today).

But the presence of the chemical handling and film application hardware inside Gambit is also an extra piece of the FROG puzzle: it indicates that the handling for the development chemistry would have been closer to a modification/duplication of an existing system rather than creation of an entirely new system.

The acoustics are more difficult during the Q&A session. My understanding is that at 01:37:18 John Shafer is talking about the manufacturing process, which involved an 1,800 ft long roller system to thin and stretch out the film base in order to get it down to the required thinness. Once this had been accomplished, the next manufacturing step  involved the roll coater.

The exposed film in GAMBIT went via the film chute directly to the take-up spool in one of the recovery vehicle. There was no on-orbit chemical processing of the film.

edit: The full film path was
Film supply spool - Film input looper - Camera  - Film output looper - Take-up spool in RV

edit 2: Here is a link briefly describing the manufacturing steps at Kodak starting with the film base (skip to 3m00s)

[Blackstar]

I had a look through the Gambit Handbook (https://www.nro.gov/Freedom-of-Information-Act-FOIA/Declassified-Records/Selected-Historically-Significant-Documents-of-Public-Interest/grsh/), but no mention of a coater or even a redacted space where description of one could be. The handbook only appears to cover G and not G*/G³ though, which is where the ultra thin base film would have come into play.

It covers the G-3. It's dated 1980.

[Blackstar]

Okay, now that we've settled that there was no film coating system inside the spacecraft, I thought I would share this presentation file on GAMBIT.

This is from 1977 and it is the best overall summary of the GAMBIT program. Looking through the NRO website, they released remarkably few GAMBIT documents. Only a few dozen. They certainly have thousands more in storage. Somebody has been periodically FOIAing the Performance Evaluation Team reports for each mission, and they have released several of those. The PETs provide a good summary of what happened on each mission. (We could probably collect those up from the NRO's website and post them here.)

An article that I have in very rough draft form is an account of the last GAMBIT missions. Another article that I have that is complete but not yet published summarizes the GAMBIT Dual Mode program. But I really want to figure out the GAMBIT engineering, not just the missions.

[Blackstar]

Some of the PET reports.

[Blackstar]

The Photographic System Handbook from 1980. Describes all aspects of the GAMBIT photographic system.

[Blackstar]

The rest of the Photographic System Handbook from 1980. Describes all aspects of the GAMBIT photographic system.

[Blackstar]

From the GAMBIT slides I posted above.

[Blackstar]

This is an aspect of the last GAMBIT spacecraft that I always thought was kinda neat: it had two cameras, or more precisely, two different rolls of film that could be exposed in the camera.

[hoku]

The MOL release includes bits&pieces on GAMBIT and GAMBIT3. The attached example is an analysis of the problems encountered at the beginning of the operational phase of either of the projects, and the initial performance.

GAMBIT started off with a best ground resolution distance of 10' to 15'. A best resolution of around 3ft was only achieved for 5 out of the first 15 GAMBIT missions. This includes a number of mission failures related to the Orbital Control Vehicle (OCV).

GAMBIT3 had the advantage of a mature OCV, but was subject to "immaturity associated with the extension of technology that is being accomplished". For the first 8 GAMBIT launches (including one booster failure) the report states "So far, the best of these tests, quite predictably, have produced photography averaging about 70 percent above the ground resolution which the mature system will achieve".

https://www.nro.gov/Portals/65/documents/foia/declass/mol/197.pdf

Note: The MOL INDEX table dates the report to early 1966, but with the reference to the first 8 G3 missions, it must be from late 1967/early 1968.

[hoku]

From the GAMBIT slides I posted above.

The more recent release of the slides (in B&W) reveals GAMBIT3 average tri-bar resolution for the years 1968-70 and 1971-73. 

I wonder why didn't include the results of the first 10 flights in 1966-67? 

[LittleBird]

Something that I have seen contradictory information about is the success of the first four GAMBIT (KH-7) missions. I think I have seen one document that indicated that "not one useable photograph" was obtained during those missions, but other reports that indicated that they worked, just not perfectly. I think that the problems may have been thermal rather than mechanical. The cameras operated, but the focus was a bit off because they had not yet solved the thermal control issues.

Ah, now I understand your remark about the thermal control sections for GAMBIT in your post on the Kodak mystery collection: https://forum.nasaspaceflight.com/index.php?topic=15459.msg2198159#msg2198159

 

By the way, has the bottom left item in the Kodak mystery collection (first grab) been identified yet ? I assumed it was a ground based mockup of the DORIAN camera-is that right ?

[Blackstar]

The MOL release includes bits&pieces on GAMBIT and GAMBIT3. The attached example is an analysis of the problems encountered at the beginning of the operational phase of either of the projects, and the initial performance.

GAMBIT started off with a best ground resolution distance of 10' to 15'. A best resolution of around 3ft was only achieved for 5 out of the first 15 GAMBIT missions. This includes a number of mission failures related to the Orbital Control Vehicle (OCV).

Buried in the CREST records database is a CIA memo, probably from late 1963, where they are practically gloating that the early GAMBIT missions didn't perform very well.

And I remember that Jeff Richelson said that the first GAMBIT missions were lousy. He probably references that in one of his books.