F-8's radar controls: A short thread on why on earth the early F-8's radar controls were so bad.
Our story actually starts with the F2H-3, the night fighter version of the F2H. In the F2H-3, the radar was controlled by a joystick and a range thumbwheel.
At this time, radars required high pilot workload. Scope gain was controlled manually, there was no search antenna stabilization, and acquisition had to be done manually by pointing the antenna at the target and placing the range gate over the target.
Short reminder of what a range gate is:
One of the problems with this was in steps four and five, as shown above. The radar could not provide heading information, so the pilot had to estimate it.
Due to estimation, acquisition was often difficult because of error in estimation and time delay before lock-on.
Because of this, pilots would often position the target close to the center of the radar screen to reduce error in estimation before beginning lock-on.
In 1951 an alternate system was proposed. With this, in the acquisition mode, target acquisition was limited to the radar boresight to allow the pilot to more easily manipulate the radar display controls and keep control of the aircraft. All he had to do was align the range gate.
This system was deemed worth the trade-offs, and so it was applied to a follow-on aircraft: the F-8 Crusader. On the F8U-1E(F-8B) and F8U-2, the first Crusaders with search and track radars, this system was used.
Obviously, this was not ideal. This could provide similar issues of lack of lock-on in extreme crossing-target scenarios. The F8U-2N(F-8D) and 2NE(F-8E) rapidly reintroduced the radar joystick controls alongside their new APQ-83/APQ-94 radars, but with a much different layout.
The main control joystick likely took design cues from Convair's F-102 and F-106 interceptors, which used a similar style of joystick/radar joystick assembly. (Photo:) flickr.com/photos/ian_e_a…
This was a much more modern system that benefitted from increased computerization in radars, allowing for simplified acquisition from search. A boresight acquisition mode that performed exactly like the previous system was retained with Automatic Range Only (ARO) mode.
This isn't particularly groundbreaking or shocking, but I've spent some time confused as to why the radar control ergonomics started out as unsatisfactory on the F-8. This is the answer!
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"Why you can trust SCMP" You can't. This is mostly hot air.
A short, less-technical thread about this article.
The first problem is that I cannot find a study that matches this description and date. I did look, but I came up empty-handed.
Xie Junwei, though, is a real person who does relevant research at "Air and Missile Defense College, Air Force Engineering University".
This is the big claim. This isn't a new thing, radar cross-sections change based on wavelength. Most fighters are optimized for X-band stealth (or other frequency bands around it), as those bands are the most relevant in fighter and missile radars.
AAM-N-3 started life sometime in the early 1950s as a replacement for the beam-riding AAM-N-2 Sparrow I, which proved to be wholly inadequate. It featured an aerodynamic redesign, and, more importantly, an active radar homing seeker.
Sparrow II: the odd one out. 🧵
Developed by Sperry-Douglas, like the first one, the second Sparrow was primarily intended to provide a better guidance system to allow for successful intercepts of maneuvering targets, or from other angles besides head or side on.
A secondary goal was the higher survivability that Sparrow II would offer to the launching aircraft, as it did not have to maintain a target lock. This was very forward-thinking, and would not be properly reconsidered until AIMVAL in the 1970s.
It's about time I re-did my AIM-4 thread on this account. The AIM-4 family, despite their poor reputation, were, in reality, very advanced missiles, despite starting life as the U.S.A.F's first operational air-to-air self-guided missile (it's also my favorite missile family).🧵
There are three major varieties of AIM-4. First, the GAR-1, the first airframe design, the GAR-1C, the second airframe design, and the GAR-3/4, the third major revision to the design. These all were designed to serve on different interceptors. (GAR-1/-1D/-3A&-4A)
Within all of these different versions, there was always a radar-guided and an infrared-guided version. The purpose of this was to improve the probability of a successful interception against a target that was either jamming or dropping flares.
HAVE DASH II, AARGM-ER, and the future of American long-range air-to-air missiles:
This is going to be an unusual thread for me, completely based on speculation and some basic knowledge about the direction of experimental programs and the goals of JATM.
AARGM-ER pictured.
This is a topic I've been giving some limited thought to for a very long time, but only recently formed an opinion on. The short version is that I think JATM will use a similar airframe to AARGM-ER, with some optimizations for maneuverability.
The first place to start is with HAVE DASH, a program to develop a low-observable missile in the 90s for use on future low-observable fighters.
Okay, well, I can't come up with any good ideas for an April Fools bit so you get a thread of some of my favorite bad/questionable missiles/missile ideas. Will update it as the day goes on if I can think of any I missed.
FIRST ONE:
Diamondback. This was described in literature as a "Nuclear Sidewinder". This is a bit silly, as it shared nothing with the real Sidewinder. 12" in diameter, it packed a nuclear warhead, likely W54 derived, with a 750t TNT equivalent yield.
I can't find much about the radar homing, but the IR was cooled and likely completely unlike that of the current Sidewinder.
Little bit of F2H-4 cockpit ergonomics as compared to the F-86K, the gun-armed Sabre Dog. These both used the same Hughes MG-4 fire control system, set up for the M24A1 or AN/M3 20mm cannon, but the F2H-4's radar controls were laid out in a much better manner. Short🧵
On both aircraft, a modified Sperry A-4 gyro lead computing gunsight was used in combination with range information provided by the radar to provide an accurate aiming point for the pilot.
However, the MG-4, a system derived from the rocket-oriented E-4 FCS, required significant heads-down operation for a successful intercept. It also required heavy operator involvement in the mechanization of the radar. So, why was the F2H-4 so much better?