Rivet Haste: Rebirth of the USAF at the end of Vietnam

Heritage Flight F-4E Phantom painted in Vietnam-era colors.

In several prior postings I had talked about how the United States set about improving the performance of its fighter pilots over the skies of Vietnam. The first one dealt with the testing and analysis of MiG fighters that had been obtained secretly by the United States and the second posting covered the origins of Red Flag, the exercises in Nevada that gave pilots valuable experience under simulated combat conditions. The Navy also instituted measures to improve its fighter pilots' performance after the Ault Report was commissioned by the Chief of Naval Operations to review naval air-to-air tactics. One thing to keep in mind is that there were numerous parallel measures being undertaken in the late 1960s and early 1970s to improve the dogfighting skills of American pilots. The main American fighter of the day that was in service with both the US Navy and USAF was the McDonnell Douglas F-4 Phantom II. The Air Force in particular, also looked at ways of improving the performance of the Phantom, a design that was originally intended for fleet air defense but found itself in swirling low speed dogfights over Vietnam for which it was never designed. 

The Phantom had two idiosyncrasies that proved to be a liability in a dogfight. Being a big hulking fighter with two J79 engines that left a nice smoke trail for the enemy to spot were one of just many faults of the aircraft. As the engines of the Phantom were optimized for high speed, so to were the aircraft's aerodynamics. In the low-speed regime during a dogfight, the F-4 was prone to what was called adverse yaw- normally when the pilot wanted to turn one direction, he only had to move the stick in that direction. At low speeds and high angles of attack that were commonplace in a dogfight, however, if a pilot pushed the stick to the left, the downward-deflected aileron on the right wing would produce more drag than lift, causing the Phantom to yaw back to the right even though the pilot wanted to turn left. As the yaw increases, the effective sweep on the left wing decreases and it starts to produce more left and the F-4 snaps to the right and then into a spin. All this happened nearly instantly and pilots had to compensate for the adverse yaw when rolling left or right by using the rudder aggressively during close air combat- instead of moving the stick into the direction of the turn, the rudder was deflected. So a left turn meant keeping the stick centered and pushing the left rudder pedal down. This causes the Phantom to yaw to the left and this decreases the effective sweep on the right wing- it therefore creates more lift and the plane now snap rolls into the direction of the turn. This took a lot of practice and it was suspected that a significant number of Phantom combat losses were due to adverse yaw conditions. 

The ergonomics of the Phantom cockpit weren't exactly great, either, with a mass of switches and dials that most Phantom drivers felt were scattered randomly over the instrument panel and side consoles. Most derided by the pilots were the switches on the panel by the pilot's left knee that controlled the Sidewinder and Sparrow missiles- one of the switches was a three-position switch that cycled through the Sidewinders and Sparrows. It felt identical to the other control switches on the missile panel and the last thing pilots wanted to do was look at the switch to make sure they flipped the right one in the middle of a dogfight. Resourceful pilots in Vietnam got hold a piece of plastic tubing that was used to sample oil from the engines. Cutting it into a two-inch length, it was slipped over the end of the switch so it stuck out from other switches. All a pilot had to do during combat was swat the tubing by his left knee to cycle through his missiles. 

South Korean F-4E shows off its leading edge slats.

When the F-4E entered service, its most obvious advantage was that it had an internal cannon in the nose, rectifying a situation often encountered in Vietnam when the MiGs were inside of the minimum launch parameters for either the Sidewinder or the Sparrow missiles. But the F-4Es had another advantage and that was what was called a "soft wing"- the wing now had leading edge slats that were controlled automatically by the flight control system whenever the angle of attack would reach a certain level. When the AoA hit this preset level, the slats would automatically pop out and it increased the lift across the wing- this had a dual effect on the Phantom- it eliminated the adverse yaw condition, even at high angles of attack. And secondly, the Phantom became practically spin proof as adverse yaw got eliminated- accidents from spins dropped dramatically and pilots could now haul around the beast in the sky without worrying about loss of control. In fact, some pilots felt that the soft wing F-4E flew just like the Northrop T-38 Talons used in advanced flight training. 

When the USAF brass got word of the improvised plastic tubing modification used in Vietnam, it became apparent after some analysis that many MiG kills were missed due to the missile switches being configured incorrectly. And truth be told, it was pretty embarrassing to know that to make a multimillion dollar fighter more effective in combat needed a cheap piece of tubing. The Air Force came out with a modification to the F-4E that was numbered 556. Pilots called it the "five-five-six mod" and what it did was add a switch on the outside of the left throttle. Operated by the pilot's left pinkie finger (hence it was called the "pinkie switch"), it if was pushed forward, the Sparrow missile was selected. If it was in the middle setting, a Sidewinder was selected. And if it was pulled all the way back, the F-4E's gun was selected. Since the pilot's hand was always on the throttles, the switch was readily accessible. The second part of the 556 mod was another switch added to the front of the left throttle that allowed the pilot to instantly reconfigure the weapons systems from air-to-ground to air-to-air. No longer was there a switch sequence to follow. Push one button, that was it. Other changes consolidated the bomb dropping switches into a single small panel. 

TISEO unit on the F-4E.

While the soft wing and the pinkie switch did much to ease the pilot's workload in air combat, there was still the issue of the rules of engagement requiring visual identification of a MiG before shooting. This restriction pretty much rendered the Sparrow useless as a beyond-visual range (BVR) weapon that could swat MiGs down from unseen distances. The biggest problem with the Sparrow with the RoE in use over Vietnam was that most engagements began head-on. At that distance, the Sparrow could be fired at a maximum of ten miles and a minimum of three miles. But head-on, the MiGs were much smaller and harder to see even if with a radar lock. With closure rates approaching one mile every three seconds, by the time the Phantom crew had a positive visual on the MiG, it was already too late to fire a Sparrow. The solution was called TISEO- Target Identification System Electro-Optical. Some F-4Es had an electro-optical telescope mounted on the leading edge of the left wing above the inboard pylon. The telescope had 4x and 10x magnification and displayed the image on the WSO's radar display. Now when the backseater had a radar lock, he could command the TISEO to track the target and then switch to 10x magnification for visual identification while the MiG was still in the firing envelope of the Sparrow missile.

With the soft wing, the pinkie switch, and the TISEO, the USAF realized it had the tools to make its fighter pilots more lethal. In the late summer of 1972, the Rivet Haste program was established. Rivet Haste would be the Air Force's acknowledgement that years of substandard training and poor doctrine had to be reversed. Rivet Haste combined the slatted wing, TISEO, and 556 mod of the F-4E and teamed them up with handpicked crews with combat experience over Vietnam. They were assembled at Nellis AFB and here the key of Rivet Haste would take place- intensive training with the new F-4Es against the secret MiG force that Air Force flew out of Tonopah north of Las Vegas. Each Rivet Haste crew were paired up to stay together through training to deployment for combat- this allowed the pilot and his WSO to develop their own system of coordination in the cockpit and carry that to combat. Six pilots and six WSOs were in each Rivet Haste group and each pilot/WSO would fly at least three missions against the MiGs at Tonopah. Each month, a new group of six pilots and six WSOs were assigned to Rivet Haste. Crews assigned to Rivet Haste saw it as a quantum leap in air combat training that the USAF had never had before, but the war in Vietnam ended less than two weeks after the first Rivet Haste crews arrived in Southeast Asia. 

It wasn't all for naught, though. The 556 mod spawned a cockpit design philosophy called HOTAS- Hands On Throttle And Stick- this meant that every function that a pilot needed in air combat (and even in air to ground combat) would be instantly accessible either on the throttle or stick. Many of the crews that were part of Rivet Haste would go on into important leadership positions in the post-Vietnam USAF that would result in a greater emphasis on realistic training. The realistic training provided to Rivet Haste crews would be one of several foundations that would result in the Red Flag exercises. 

As the saying today goes "Fight like you train, train like you fight". 

Source: Sierra Hotel: Flying Air Force Fighters in the Decade After Vietnam by C.R. Anderegg. Air Force History and Museums Program, 2001, p11-13, 32-35.

The Origins of Red Flag

I had started this blog out as a way of sharing a lot of the interesting aviation history I come across in the course of my reading. I'm a bit attention-deficit when it comes to reading, I usually jump between numerous books at once as I've really never been able to read one book straight through then start another. The benefit of this little quirk of mine is that what I post in this blog can be quite varied. Most of the time as I'm reading, I'll put a little dog ear on pages that I think have good material for this blog and over time, you can guess that most of my aviation books have little dog ears in the lower corners. I'll have several possible topics rattling around in my head at any given time and then when I have the chance to sit down and start a post, it's just a matter of seeing which one topic I've been ruminating over comes easiest to type! The topic I had planned for today got postponed as I learned via my regular Twitter stream this morning that on this date thirty-five years ago the first Red Flag exercise was held at Nellis AFB, Nevada. I just happen to be currently reading Steve Davies' wonderfully engaging book Red Eagles: America's Secret MiGs and it details the origins of the now-famous combat aircraft exercise that is held several times a year at Nellis. 

This past weekend I had posted about those first secret MiGs that operated out of Area 51/Groom Lake. The operational exploitation of the MiGs was but one of the first steps taken by the US Air Force and the US Navy to reverse the sagging fortunes of US fighter pilots over the skies of Vietnam. In 1966 the Tactical Fighter Weapons Center (TFWC) was established at Nellis AFB as the leading school house of fighter tactics evaluation and training. One of the keys to the TFWC was making use of the 12,000 square miles of uninhabited desert terrain north of Nellis that gave in the words of Steve Davies "the playground for America's finest fighter pilots". One of the earliest projects based out of the TFWC was the "Red Baron" reports. Since 1966 the Department of Defense's Weapon Systems Evaluation Group had been collecting a wealth of information on every one of the 320 MiG encounters in Vietnam until July 1967 that involved either the McDonnell F-4 Phantom or the Vought F-8 Crusader. That exhaustive data set became Volume I of Red Baron. Volumes II and III analyzed another 259 MiG encounters by Republic F-105 Thunderchiefs as well as other US aircraft. That three-volume set of data became Red Baron I. In 1969, Red Baron II covered 625 MiG encounters from 1967 to the end of Operation Rolling Thunder at the end of 1968. Later, Red Baron III completed the comprehensive analysis of the air war. 

The Red Baron reports were incredibly detailed with interviews of crew members and pilots with questions to be answered such as "Where were you when you first saw the bogeys?" or "What altitudes and speeds were being used in setting up the engagement?". The bottom line of the Red Baron reports was quite simply that American fighter pilots in Vietnam were not familiar enough with fighting dissimilar aircraft- what was needed was DACT- Dissimilar Air Combat Training. Red Baron went even further, recommending that the USAF provide its fighter pilots with realistic enough training based on the detailed study of all of the MiG encounters in the classified reports. One recommendation was the use of actual enemy aircraft (which stemmed from the programs I posted about this weekend) or realistic substitutes. That recommendation led to the formation of the USAF Aggressors, units operating Northrop T-38 Talon trainers and F-5E Tiger II fighters as surrogates for enemy MiGs. The pilots of the Aggressors specialized in emulating Soviet tactics, even using their own organic GCI controllers. 

The first Aggressor squadron stood up at Nellis AFB in the summer of 1972, but some of the founders and proponents of the Aggressors wanted to push the training even further. While the first Aggressor squadrons were wildly successful to the point that two overseas Aggressor squadrons were established (one in the Philippines at Clark AB for PACAF and one at RAF Alconbury for USAFE), it was a well-known fact from the Red Baron reports that new fighter pilots in the skies over Vietnam had a disproportionately low life expectancy. Other USAF studies had shown that the majority of combat losses (even outside of Vietnam) occurred within a new pilot's first ten combat missions. Once getting the eleventh combat mission, a new pilot's survival chances quickly improved due to experience. The solution was an elegant one that dovetailed nicely with the mission of Nellis AFB, that of the Aggressors as well as the secret MiG force then based at Area 51/Groom Lake. Recreate the first ten combat missions for pilots in the training environment at Nellis AFB using not only the Aggressors and the MiGs, but also the air-to-ground ranges to improve the accuracy of strike aircraft crews. In May 1975, the Tactical Air Command commander, General Robert J. Dixon, gave his approval for the formation of Red Flag with the first exercises to be held in six months. 

In that hectic six months, the most realistic training environment was created at the weapons ranges north of Nellis AFB. Not only were there to be fighter and strike aircraft, but also electronic warfare aircraft, transports and tankers. Reconnaissance assets would participate. Captured Soviet radar systems and facsimilies were arrayed in the ranges along with an integrated missile and anti-aircraft gun defense system. Targets were laid out and finally, the Aggressors would play the part of enemy MiGs (eventually even the secret MiG force participated). Right on schedule, on 29 November 1975, Red Flag I took place with 37 aircraft, 561 personnel and a total of 552 sorties were flown.

Today's Red Flag is a three week exercise in which entire squadrons deploy with their maintenance and support personnel as if on a wartime deployment. The average Red Flag exercise will have around 100 aircraft with several thousand personnel. Units from all branches of the US military participate as well as Allied nations where an invitation to Red Flag is considered an honor and testament to a foreign unit's professionalism. Since that first Red Flag exercise thirty-five years ago today, it's estimated that over half-a-million personnel have been trained, over 300 types of aircraft have participated and well over thiry nations have participated. 

Source: Red Eagles: America's Secret MiGs by Steve Davies. Osprey Publishing, 2008, p24-37.