I remember hearing that Grumman had serious problems with the A-6 on the production lines due to it's highly advanced electronics and it having both air-to-air and air-to-ground radars.
Assuming it is not classified, does anyone have any specifics on the problems or how serious it was?
The A-6F would have come with the air-to-air capable AN/APQ-173 but it never reached the fleet. The A-6G upgrade program also included this air-to-air capability but was never funded. (Because, you know, A-12 coming. Then, of course, peace dividend.)
I wonder if any of the later upgrades included an AA mode?
Weren't the issues related to the early versions of the Vertical Display Indicator (VDI) by Kaiser, with its very early incarnation of 'augmented reality'?
The A-6 from the start had a Vertical Display Indicator (VDI) for the pilot. This cathode ray tube display screen used data from the search radar and provided a synthetic representation of the world in front of the aircraft (enabling terrain-following flight, as it showed hills etc in front along with their relative height above or below the flight path), along with steering cues provided by the BN, enabling head-down navigation and attack at night and in all weather conditions.
The VDI was in the instrument panel, not above it - therefore it was not a HUD.
The projected-display item above the pilot's console was for the radar-aided gunsight - not to display flight info.
A-6A cockpit, gunsight in green box - the B/N's removable rubber hood is to keep the radar display from blinding the pilot at night:
The A-6A was built around the complex and advanced DIANE (Digital Integrated Attack/Navigation Equipment) suite. It had separate search and attack radars, a radar-altimeter, and a doppler navigation radar that provided in-flight updates to its inertial navigation system. It had 2 computers - an air-data computer and a ballistics computer.
When it worked, DIANE was perhaps the most capable navigation/attack system of its era, but the ballistics computer (a late 1950s-era rotating-drum type) was never very reliable - some part of the system would develop errors in about 1/3-1/4 of flights, forcing that aircraft to either deploy its ordnance manually or by following an A-6 whose system was working and copying its attack run.
For most of its service the A-6A was recipient of regular "fixes" to DIANE.
Some A-6As had a second display for the output from the ballistics computer for the pilot under the VDI, others did not. The A-6E also lacked this display.
A-6A without second pilot's display:
In 1972 the first A-6Es were delivered - these had a much-improved CAINS (Carrier Aircraft Inertial Navigation System), a new combined search-track radar, and a new solid-state IC-based* digital computer (basically a mil-spec IBM-360).
The A-6E got a FLIR/laser targeting/guidance system from 1979 on.
A-6E cockpit with FLIR/TV display above radar display and with pilot's gunsight:
Later A-6E's with the SWIP upgrade (1990+) did get a real HUD:
The A-6A was provided with automatic diagnostic systems, some of the earliest computer-based analytic equipment developed for aircraft. These were known as Basic Automated Checkout Equipment, or BACE (pronounced "base"). There were two levels, known as "Line BACE" to identify specific malfunctioning systems in the aircraft, while in the hangar or on the flight line; and "Shop BACE", to exercise and analyze individual malfunctioning systems in the maintenance shop. This equipment was manufactured by Litton Industries. Together, the BACE systems greatly reduced the Maintenance Man-Hours per Flight Hour.
The system was kept and improved for the A-6E.
The original computers used separate transistors and some tubes, the IBM used integrated-circuit components - mostly in the DIP (dual in-line package) form.
The IBM-360 didn't use ICs It used an intermediate precursor step between discrete transistors and digital ICs with this technology being IBM's SLT modules, this System-360 hardware design was also used for the Saturn IB/V LVDC too.
Reading your post reminded me of the 1991 film "Flight of the Intruder" where the DIANE's CRT displays were on full view (I was impressed by how sophisticated it was for the time)
The IBM-360 didn't use ICs It used an intermediate precursor step between discrete transistors and digital ICs with this technology being IBM's SLT modules, this System-360 hardware design was also used for the Saturn IB/V LVDC too.
Reading your post reminded me of the 1991 film "Flight of the Intruder" where the DIANE's CRT displays were on full view (I was impressed by how sophisticated it was for the time)
I don't know what the SLTs looked like (having not seen them, as stated above), but the circuit boards had a number of metal foil-covered shapes (square or rectangular) that varied from 1" to 3" on a side and were 1/4" high and had lots of pins entering the pcb from under the device, mixed in and around a lot of normal 16-pin DIP ICs. The circuit diagrams in the bench repair manual only showed them as blank spaces with the pins labeled, whereas the internal diagrams for the ICs were freely available (being commercial standard chips).
The computer for the AAM-60 was a HP 1000 minicomputer, installed in the racking of the bench (the terminal was on a separate rolling stand).
At the USMC A-6 AIMD facilities we had the AAM-60(V)4, which was set up for the A-6's AN/AAS-33 Target Recognition Attack Multisensor (TRAM) system (Hughes) only.
The (V)1 was for the P-3 Orion's AN/AAS-36 FLIR (Texas Instruments infrared detection system [IRDS]). It did not have the right-hand bay or an actual computer - it was operated by punching in combinations of the buttons in the panel below the oscilloscope.
The (V)2 was for the S-3 Viking's OR-89 FLIR (Texas Instruments) and was also push-button 3-bay.
The (V)3 was for the OV-10D NOS's AN/AAS-37 FLIR/laser (Texas Instruments), and was also push-button 3-bay.
The (V)5 was for the A-7's AN-AAR-45 LANA (Low-Altitude Night Attack) FLIR pod (Texas Instruments) only, and had the 4th bay and the computer.
The (V)6 was for the A-6, A-7, AND S-3 FLIRs, and was the standard carrier fit.
AN/AAM-60(V)4 at H&MS-12, MCAS Iwakuni, Japan summer of 1984 - the yellow tag is hanging from the HP-1000:
With A-6E FLIR turret in maintenance cart. Note the cable adapter array on the test bench has a black cover over it:
Note the cable bundles above & beside the adapters (top for full unit test, middle for laser test, bottom for self-test):
Me taking an old-fashioned selfie in the FLIR sensor's window:
Solid Logic Technology (SLT) was IBM's method for hybrid packaging of electronic circuitry introduced in 1964 with the IBM System/360 series of computers. It was also used in the 1130, announced in 1965. IBM chose to design custom hybrid circuits using discrete, flip chip-mounted, glass-encapsulated transistors and diodes, with silk-screenedresistors on a ceramic substrate, forming an SLT module. The circuits were either encapsulated in plastic or covered with a metal lid. Several of these SLT modules (20 in the image on the right) were then mounted on a small multi-layer printed circuit board to make an SLT card. Each SLT card had a socket on one edge that plugged into pins on the computer's backplane (the exact reverse of how most other companies' modules were mounted).
IBM considered monolithic integrated circuit technology too immature at the time.[1]SLT was a revolutionary technology for 1964, with much higher circuit densities and improved reliability over earlier packaging techniques such as the Standard Modular System. It helped propel the IBM System/360 mainframe family to overwhelming success during the 1960s. SLT research produced ball chip assembly, wafer bumping, trimmed thick-film resistors, printed discrete functions, chip capacitors and one of the first volume uses of hybrid thick-film technology.
SLT used silicon planar glass-encapsulated transistors and diodes.[2]
SLT uses dual diode chips and individual transistor chips each approximately 0.025 inches (0.64 mm) square.[3]: 15 The chips are mounted on a 0.5 inches (13 mm) square substrate with silk-screened resistors and printed connections. The whole is encapsulated to form a 0.5 inches (13 mm) square module. Up to 36 modules are mounted on each card, though a few card types had just discrete components and no modules. Cards plug into boards which are connected to form gates which form frames.[3]: 15
SLT voltage levels, logic low to logic high, varied by circuit speed:[3]: 16
High speed (5-10 ns) 0.9 to 3.0 VMedium speed (30 ns) 0.0 to 3.0 VLow speed (700 ns) 0.0 to 12.0 V
but the circuit boards had a number of metal foil-covered shapes (square or rectangular) that varied from 1" to 3" on a side and were 1/4" high, mixed in and around a lot of normal 16-pin DIP ICs. The circuit diagrams in the bench repair manual only showed them as blank spaces with the pins labeled, whereas the internal diagrams for the ICs were freely available (being commercial standard chips).
We were told by the Boeing tech-rep we had when we set up the shop in El Toro in the spring of 1983 (using the AAM-60 that Hughes had used to develop the AAS-33 test programs) that shortly after Boeing had certified that the bench worked right, they ordered a set of circuit cards (about 20 per bench, 8" x 12") for all planned benches plus spares and then fired the contract engineer who had designed them.
This caused a major problem, as he had been hired on a contract that let him retain copyright/patent rights to his work, and he had taken ALL of the engineering plans and info with him when he left (and he had gotten the manufacturing plans from the maker as well) leaving Boeing with NO idea of exactly what the circuits inside the devices actually were.
If any of those devices ever failed we were supposed to send the whole board back to Boeing (there were spare boards) for their engineers to try to reverse-engineer... but in over 6 years on land, aboard ship, and even flying H&MS-12's bench back and forth between MCAS Iwakuni, Japan and NAS Cubi Point, Philipines I never saw even one fail.
and then fired the contract engineer who had designed them.
This caused a major problem, as he had been hired on a contract that let him retain copyright/patent rights to his work, and he had taken ALL of the engineering plans and info with him when he left (and he had gotten the manufacturing plans from the maker as well) leaving Boeing with NO idea of exactly what the circuits inside the devices actually were.
Now, THAT, was an incredibly short-sighted act of stupidity, I hope the Boeing execs who dismissed the engineer in turn lost their own jobs as a result. I wonder if Boeing tried to buy the designs from the engineer?
Some A-6As had a second display for the output from the ballistics computer for the pilot under the VDI, others did not. The A-6E also lacked this display.
A-6A without second pilot's display:
Awesome description of the variants and avionics suites. Thank you.
Actually, were all A-6As fitted with the PHD CRT display under the VDI as shown on the sketches below? The manual of the A-6ABC/ KA-6D/ A-6E is inconclusive on the matter. Your second photo suggests an upgraded A-6A version from the early-/mid-1970s.
Reading your post reminded me of the 1991 film "Flight of the Intruder" where the DIANE's CRT displays were on full view (I was impressed by how sophisticated it was for the time)
The original manual does not indicate any sophistication of the 'augmented reality' presented on the VDI. The "Flight of the Intruder" movie likely showed something generated on 8- or 16-bit personal computers or a very late incarnation of the VDI.
Aircraft photo of 156981 / ND-610 - Grumman EA-6A Intruder (G-128/A2F-1Q) - USA - Navy (VAQ-309), taken by Gary Vincent at Oak Harbor - Whidbey Island NAS / Ault Field (KNUW / NUW) in Washington, United States in August 1983. The electronic countermeasures version of the Intruder was originally...
www.airhistory.net
If the aircraft was operational in 1991, it has already been deeply upgraded. The remote LED frequency display from an AN/ARC-159 UHF COM can be seen glowing red on a still from the movie. Obviously, this radio was rather introduced a bit later than 1972, which the movie plot depicted. When the protagonists' Intruder engine flamed out, and all CRT-based systems went out, only analog instruments and that LED frequency display remained glowing, which is quite plausible in such a situation.
A chopped-off A-6E cockpit was also employed during movie production.
Here's a scene from "Flight of the Intruder" where they on their unauthorised strike of Sam City and it shows some cockpit footage:
When I saw the film in 1991 it blew me away that the A-6 had video displays (Starting at 1:31 into the clip) of that sophistication in late 1972/early 1973.
Now, THAT, was an incredibly short-sighted act of stupidity, I hope the Boeing execs who dismissed the engineer in turn lost their own jobs as a result. I wonder if Boeing tried to buy the designs from the engineer?
It's a pretty common commercial error when dealing with outsourced engineering services. Contract are drafted for a task. All data that are not generated in-house (think intellectual activities like hand calculation, FEA that have not been specified for cost grounds etc..) to achieve stated deliverables remain the property of the business or individual, unless specifically mentioned as such (hence specified as a separate transaction).
You often find genius that see rather correctly they can dispense for the last leg of the journey of the service provider just to find themselves naked without the data to correctly generate upgrades or a bit more than the final part of the work (in general you have developed tools, methodologies for that to be done that are not even specific to the project and can't then be handed over).
The law is pretty clear. It sides along who owns the IP. But still, imbeciles are found here and there.
If it was filmed in a real cockpit, then it was already upgraded with more contemporary avionics than used in 1972, eg. the ARC-159 UHF radio, which clearly shows 261.350 MHz glowing on the red LED remote frequency display on the instrument panel.
When it worked, DIANE was perhaps the most capable navigation/attack system of its era, but the ballistics computer (a late 1950s-era rotating-drum type) was never very reliable - some part of the system would develop errors in about 1/3-1/4 of flights, forcing that aircraft to either deploy its ordnance manually or by following an A-6 whose system was working and copying its attack run.
I was intrigued by your description of DIANE. According to the flight manual, starting from A-6A, the nav/attack system was built around the Litton ASQ-61 integrator. Was the trouble making electro-mechanical ballistics computer that you mentioned a part of the ASQ-61, or a separate unit (box) slaved to ASQ-61?
The above diagram suggests that only TACAN and UHF DF were separated from DIANE.
I think you mean electromechanical ballistics computer, from what little I understand about the initial DIANE system is that it mostly used cutting-edge discrete transistor analogue circuitry in its design.
I think you mean electromechanical ballistics computer, from what little I understand about the initial DIANE system is that it mostly used cutting-edge discrete transistor analogue circuitry in its design.
You're absolutely right. DIANE was electro-mechanical.
I was too focused on its mechanical part given that the character portrayed by Mr Dafoe was kicking the control pedestal to release jammed mechanics of DIANE.
You're absolutely right. DIANE was electro-mechanical.
I was too focused on its mechanical part given that the character portrayed by Mr Dafoe was kicking the control pedestal to release jammed mechanics of DIANE.
Is it just me or is there a quick cut to some short barrel howitzers firing at 5:36 in that video? I'm not quite sure what those large diameter stubby barrels are supposed to represent in terms of anti-aircraft artillery? It sure looks like someone threw in some closeups of WWII era howitzers or even pack howitzers to represent flak guns.
Is it just me or is there a quick cut to some short barrel howitzers firing at 5:36 in that video? I'm not quite sure what those large diameter stubby barrels are supposed to represent in terms of anti-aircraft artillery? It sure looks like someone threw in some closeups of WWII era howitzers or even pack howitzers to represent flak guns.
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