A recent AOPA ePilot newsletter included a segment about an incident where a female flight instructor and her student were killed accomplishing spin training. Preliminary indications are that the larger male student may have frozen at the controls during a spin recovery. Additionally, the August 2009 Instructor Report (AOPA member sign-in required) from Flight Training Magazine discusses the psychology of spin training. Both of these articles took me back to my T-37 instructor days and our spin training sessions.
My second assignment as a USAF pilot (back in the mid 1970s) was as a T-37 instructor at Webb AFB, TX. At that time all students attending USAF Undergraduate Pilot Training (UPT) started with an orientation in the Cessna T-41 (Cessna 172 variant), then progressed to the T-37, side-by-side jet trainer and finished up with the tandem-seat, supersonic Northrop T-38. The T-37 was a fun plane to fly. It wasn’t a super-fast airplane, but in my opinion that made it much more fun to fly. Aerobatics took fewer g’s and less altitude to complete than the T-38. Then there were the spins. The training syllabus in the T-37 included spin entry and recovery while the T-38 training only included various types of stalls.
I have no idea whether spin training is still part of the Undergraduate Pilot Training (UPT) syllabus. I see now that the T-37 will be officially retired from the USAF inventory at the end of the month ( 31 July 2009). It has been replaced by the turboprop Raytheon/Beechcraft T-6 Texan II. The end of an era, for sure. The T-37 began training USAF pilot training students in 1957.
In order to instruct at one of the Air Force’s primary training facilities it was necessary to graduate from the Pilot Instructor Training Course (PIT) conducted at Randolph AFB, San Antonio, TX. The courses were aircraft-specific and if you were going to be a T-37 instructor the course included enough spin training to insure that you could adequately explain the aerodynamics of a spin and, while spinning the aircraft, talk through the recovery process describing the aircraft’s reactions to each step of the recovery. After about a week of training in spins we were fairly confident of our ability to get into and out of one in the training environment and how to avoid experiencing one inadvertently.
When we practiced spins we first had to climb to at least 20,000’ AGL. In west Texas where I was an instructor that meant climbing to about 23,000 feet MSL. Since the T-37 is an unpressurized aircraft, our maximum altitude was 25,000’ MSL, so we were pushing our limits. The reason we had to be that high to enter a spin was that once the spin was fully stabilized the T-37 descended vertically at about 10,000 fpm. That gave you about 2 minutes to exit the spin or it would stop rotating on it’s own when it hit the ground. It was quite the ride.
Here is an excerpt from Bud Davisson’s article on his AirBum web site.that describes his T-37 spin experience for an Air Progress article:
So, we did a few spins. Ron [the instructor flying with Bud] declined demonstrating even one. He just cautioned me about doing the recovery exactly right and away we went. At our weight, the stall happened at about 75 knots and I stomped rudder and sucked the stick back as it broke. The outside wing snapped over the top and we twisted down into the first several turns. In the first turn the nose went down and then came back up almost to the horizon and then went down again. It oscillated like that several times before it settled down into a surprisingly flat attitude (compared to a C-150 or Cub). The recovery is something right out of a NASA handbook. You bang the opposite rudder to the floor, wait one turn (which ain’t long) then nail the stick to the forward stop-ALL the way forward. For a second, the spin appears to speed up. It whips through about a turn and a half and suddenly bangs to a stop. At that point, you’ve got to be on your toes …
Bud doesn’t relate the actual spin recovery steps. It’s amazing that after 35 years I can still recite the recovery steps. They were:
Throttles – Idle
Rudder and Ailerons – Neutral
Stick – Abruptly Full Aft and Hold
Rudder – Abruptly apply Full Rudder Opposite the Direction of the Spin and Hold
One Turn After Applying Opposite Rudder – Stick Abruptly Full Forward
Controls Neutral and recover from the Dive
The first three steps were designed to get the aircraft in the same starting point for each recovery attempt. They establish the aircraft a more or less stabilized spin condition. Between steps 3 and 4 you had to figure out which direction you were spinning. In theory you should know the spin direction since you’re the one who started the spin in the first place, but as a student in the heat of battle, that might just slip your mind, especially when the aircraft starts whipping around. The intent was to provide a sequence of steps in case a spin was entered inadvertently. As I remember, in a stabilized spin the T-37 rotated at about 3 seconds per turn with the nose dropping to about 30 degrees down once it stabilized. The spin axis was on a vertical line that passed through the cockpit between the two seats. If you referenced the turn needle you could determine the direction of rotation, but if you looked at the slip/skid ball the instrument on the left side of the cockpit would have the ball to the left and the instrument on the right side of the cockpit would have it’s ball to the right. One thing that you needed to do at step 4 was to pick some point on the horizon or on the ground when you slammed in full rudder travel opposite the spin direction. The next step was to patiently(?) wait as the aircraft rotated until that point reappeared in front of you. This was an excellent way to experience time slowing to a crawl with an adrenaline rush. When your point finally reappeared you would immediately try to push the stick forward through the instrument panel, the nose would pitch down toward vertical and you would recover from the dive.
The application of the rudder opposite to the spin direction would start the recovery and, in some cases, could actually stop the spin rotation. Unfortunately, the students rarely noticed the rotation coming to a stop. On those planes, instead of accomplishing step 5 you could just move the stick to a slightly nose down position, the stall would be broken and the plane would recover. Again, in the heat of the battle, the student would be focused only on waiting for that rudder application point to reappear and wouldn’t sense the spin rotation slowing. I remember one myopic student getting to step 5 just as the rotation stopped. I tried yelling “NO!” but I doubt if he heard me. He slammed the stick to the forward stop just as the aircraft had regained almost full control effectiveness. I had to check my helmet when we got back to the base to make sure I hadn’t cracked it when my head hit the canopy. The average T-37 would merely slow it’s rotation slightly with the opposite rudder applied and then step 5 would pitch the nose down to vertical, breaking the stall. The requirement for step 6 would then be quickly obvious as the airspeed would build quickly if the nose wasn’t immediately raised to the horizon.
In the T-37, if a student froze at the controls during a spin recovery we had two or three options for regaining their attention. We wore helmets and oxygen masks with an intercom system connecting the two headsets and sat side-by-side in the cockpit. If yelling as loud as you could didn’t bring the student back to reality we could slap the student a few times on the side of the helmet. The half-inch thick aircraft checklist with it’s metal rings worked well. If that wasn’t enough, our next-to-last resort was to grab the oxygen hose that lead to their mask and kink the hose. The inability to breathe would usually get their attention or transfer the student’s fixation from the ground rushing up at them to finding air to breathe. The last resort was ‘Handles-Raise, Triggers – Squeeze’, the ejection sequence.
In part two we’ll find out how I found myself in an inverted spin with both engines shut off.