F-104 Development

[Zipper730]

I could use some clarification on this matter: It was said the F-104 was inspired when C.L. "Kelly" Johnson and a representative from North American visited a fighter-base in Korea in late 1951: From what I remember, pilots were complaining about the MiG-15's superior rate of climb, acceleration, probably maneuverability, and the overcomplexity of their aircraft. While, I'm not sure if this was just F-86 pilots, or pilots of the F-80's and F-84's as well, or pilots and crew chiefs, but there seemed to be an objection to the hydraulic flight-controls the F-86 had, and the radar-directed gyroscopically-stabilized gunsight.

I'm not sure why pilots were objecting to hydraulically boosted controls unless it had to do with an objection to their complexity and/or the different feedback that the q-feel systems produced over the earlier un-powered flight-controls. As for the gunsight: I'm not sure how difficult the radar-directed sight was to use (though I remember hearing that more automation was added later on, so that might have been the objection), but some even objected to the gyro-gunsight (my guess is that their eyeballs and brain were outperforming the electromechanical computer used for the purpose).

The overarching desire seemed to be superior acceleration, higher top-speed, superior climb, and altitude capability to any plane that currently existed. I'm pretty sure they wanted a good degree of agility, while they were at it as well, whether they said it or not. I'm not sure if any of the USAF top-brass really took the idea of developing a future aircraft without hydraulics, gyroscopically stabilized gunsights, or radar, but it did appear, they were willing to sacrifice some systems in the interest of losing weight and building up performance.

Some later said that the airplane was designed predominantly as an interceptor first and foremost, but that conflicts with the basic history often cited for the F-104 (unless it's wrong): It does appear that at some point in the design, the USAF did want some kind of interceptor capability built into the aircraft. While the performance of the airplane (acceleration/speed/climb/altitude) were naturally conducive to the interceptor mission, generally there was a desire for some all-weather capability in interceptor aircraft (that said, I'm not sure if they wanted it to be as capable as the F-102 as originally intended, or merely a traditional fighter, that also had a decent interceptor capability built in -- even if it wasn't the best). This decision might have occurred as early as 1952, which would have been a few months into the F-104's development. Interestingly, the F-104's radar was fairly simple overall and, while it carried missiles, I'm not sure when that decision was made, though the USAF was directed to adopt the GAR-8/AIM-9 in 1955.

While I don't know what original speed requirements they sought, I wouldn't be surprised if it increased to a degree throughout the aircraft's development with a minimum speed specified, and a higher speed desired. At some point they aimed for an aircraft with a top-speed in excess of Mach 2, and the ability to fly at Mach 2 for an extended period of time (though I don't know how long "extended" meant).

buffnut453 , FLYBOYJ , X XBe02Drvr

 

[XBe02Drvr]

The overarching desire seemed to be superior acceleration, higher top-speed, superior climb, and altitude capability to any plane that currently existed. I'm pretty sure they wanted a good degree of agility, while they were at it as well, whether they said it or not.

I think they discovered that even with the mighty J79 they couldn't have their cake and eat it too. You could have Me163 style speed, acceleration, and climb, but at the expense of P51 style endurance and range, as well as Spitfire style agility. Given the atmosphere of the times, with Tu4 and Tu95 paranoia running rampant, the SAGE system in the pipeline, and promising developments in missiles and radar threatening to render dogfighting obsolete, it seems to have just made good sense to take the stellar performance of the J79 and turn it into an Me163 clone. With SAGE and GCI doing the heavy lifting for target detection and acquisition, the interceptor doesn't have to surrender its sleek profile to the large radar dish that a longer range radar would require. They even called it "The missile with a man in it".
The brave new world of nuclear armageddon wasn't going to require the mission profiles of Sabres patrolling MiG alley dating from "the last conventional war ever to be fought".

 

[Zipper730]

I think they discovered that even with the mighty J79 they couldn't have their cake and eat it too.

I'm not sure when they selected the J79 as a powerplant, but this seemed to be during the plane's development, and way before it's first flight. The plane first flew in 1954, and this was around 1952 that the desire for an interceptor came into play.

I'm not sure as the plane was being developed what proposals there were for carrying missiles. I've never seen any images depicting them with AIM-4's.

As for SAGE, it first came online in 1953 and was probably being developed for some time, but the datalink capability didn't appear available until the late 1950's. It was under development, however. Regardless, the radar the Deuce and Six had weren't that large (antenna) and, with the climate of the time, I'm surprised they didn't want a more sophisticated radar and fire-control system -- at least the plane kept it's gun.

 

[XBe02Drvr]

Regardless, the radar the Deuce and Six had weren't that large (antenna) and, with the climate of the time, I'm surprised they didn't want a more sophisticated radar and fire-control system

USAF was big on Ground Controlled Intercept, so didn't see the need to clutter up the nose of a high performance jet with a big dish long range radar. All that was needed was a close range fire control system.

 

[MIflyer]

The F-86 was known for excellent maneuverability and the adjustable horizontal tail was a great success. It was also mostly faster than the Mig-15, although not at all altitudes. The early F-86's could break the sound barrier in a dive; try as they might the Air Force never got that captured Mig-15 to do that.

The APG-30 radar gunsight was a great success, too. All it did was eliminate the need for the pilot to adjust the ring on the gunsight to match the wingspan of the target aircraft in order to get a range number.

The Mig-15 could climb higher and faster, and that is what the pilots wanted.

 

[Peter Gunn]

"but there seemed to be an objection to the hydraulic flight-controls the F-86 had, and the radar-directed gyroscopically-stabilized gunsight."

Said no Sabre pilot ever. In all the reading and speaking to Sabre pilots from the Korean "Police Action", I've never heard of this, not saying it isn't a possibility but...

 

[XBe02Drvr]

"but there seemed to be an objection to the hydraulic flight-controls the F-86 had, and the radar-directed gyroscopically-stabilized gunsight."

Said no Sabre pilot ever. In all the reading and speaking to Sabre pilots from the Korean "Police Action", I've never heard of this, not saying it isn't a possibility but...

In my experience, in most any corner of the aviation world you can find a few curmudgeons who think the older, simpler, ways were better than the newfangled gee-whiz stuff. And given the imperfections of some of the early versions of hydraulically boosted controls, I can easily envision WWII piston fighter pilots recalled to service and hastily qualified in jets being a little leery of the newfangled stuff. In fact, I've spoken with a couple back in the day. "There's no "feel" to the controls!" "It's like your stick is issuing verbal commands to control surfaces that have a limited grasp of English!"

 

[pbehn]

. "There's no "feel" to the controls!" "It's like your stick is issuing verbal commands to control surfaces that have a limited grasp of English!"

Maybe like early power steering in some cars, some was so over boosted you could turn the steering as fast as you liked, regardless of how fast you were going. Nice and light and no one would ever get tired but would also turn the wheels on a motorway leaving the car with howling tyres still going straight on.

 

[MIflyer]

A friend of mine, a Vietnam helicopter pilot, said he often had to clean the windshield on Cobras because previous crews had made grease pencil aiming marks.

And yes, my first car was a 1965 Dodge Coronet with 318 V-8 and "fingertip" power steering. Transitioning to that from a 1963 VW Bug brought on a lot of Pilot Induced Oscillations during turns until I got the hang of it. And if it was a cold night and that engine quit after slowing up for a turn then you were along for the ride, the steering wheel being set in concrete.

 

[Lyall]

Kelly Johnson considered what he was doing an air superiority fighter not a point defense interceptor. The feedback he got from his Korea trip was that pilots wanted more acceleration, speed, and climb capability. I think Grabreski was the guy who complained about the lead computing sight in the F-86 saying he do as well with a piece of chewing gum on the windscreen hence the "Gumsight" joke. The idea was to go above the enemy and come right back down on them. Which kind of describes how the Mig-15s operated. I don't reading anything about agility being considered in the design just less complex and lighter. It did have a very good control system and the USAF would recommend to other manufacturers to do it like the F-104's. Kind of like the USN and the FJ-3. The F-104 was moved into interceptor roll temporarily because the F-102 & F-106 were both behind schedule which also led to the F-101B.