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Texan Aerobatics - In The Metal By Derek Swanson 27 May 2009 As a UK simmer (but not a real-world pilot) I often try and perform aerobatic manoeuvres to test the flight dynamics of a new aircraft or just for fun, but just recently I was able to enjoy a full hour of it for real - in a North American T6 Texan. This came about due our family having several significant birthdays in 2008; mine (the half century) being one of them, so we decided on a holiday in Florida. I received a number of monetary gifts so decided to blow it all on a flight with Warbird Adventures in Kissimmee, Florida. Having planned quite a full theme park itinerary for the holiday (two teenage children to occupy) I selected a "rest" day for my flight and booking it with Warbird Adventures, which was very simple. I rang them up from my Florida apartment and chose the day, taking their recommendation of a 9 am flight as the weather would be better at that time. Kissimmee airport is situated very near the major Florida attractions and offers a number of airport and aircraft services including business flying, flying training and aircraft repair and restoration. Warbird Adventures not only offers pleasure flights but also has a museum that includes a working aircraft restoration hangar running several different aircraft restoration projects. I arrived a little early for the flight so had the opportunity to browse the museum, which actually meant unrestricted access to the hangar and its very interesting contents. Private and pleasure flying in the USA is refreshingly different than its equivalent back home in Blighty and I discovered this at the "check-in". I was expecting a long rigmarole filling in a number of forms and a mandatory "ground school" session, something I'd previously experienced with a trial flight at a UK flying school. What I received at Kissimmee couldn't be more different. First a short and very informal chat with the receptionist (also a pilot), then one simple form to be signed and a swipe of the credit card - I was ready. While the aircraft was being prepared I was able to watch the process on the apron. Wardbirds have three Texans but only one was serviceable for my flight. One was in the hangar for a minor repair - the replacement of the landing light following a bird strike; the other was in several pieces, undergoing a major overhaul. Having completed his checks, my instructor Sean introduced himself and invited me to do a walk around and board the plane. Sean guided my access into the front (student) cockpit and then strapped me into the seat-pan parachute and the seat harness. Having checked the tension of my straps he gave me some simple, almost nonchalant advice about baling out - "If there's a problem I can't fix I'll call 'bale out' three times. Open the canopy with your right hand (it's very awkward with the left and you won't do it); release the seat harness, not the parachute harness, and climb out of the cockpit. If you can, go out the right hand side." Leaning into the cockpit Sean then talked me through the flight controls and instruments and my simming experience helped reduce this instruction session considerably. One interesting point was that because this plane spends most of its time doing aerobatics, the attitude indicator (AI) and vertical speed indicator (VSI) are both disconnected since the repeated looping and rolling movements of the plane result in excessive wear. Recalibrating or replacing these instruments is expensive. One other aspect of this plane relevant to its current role is the fitting of small cameras for video recording the flight. There are four altogether, one in each wingtip facing the cockpit, one on top of the fin facing forward and one under the front instrument panel facing upwards to the pilot (soon to be me). The appropriate camera selection is made by the instructor to record the aerobatic manoeuvres for posterity. Sean climbed into the rear (instructor) cockpit switched on the intercom and started the engine. After Sean had checked the various engine gauges were in range, the adventure began. Taxiing out of the apron and down the taxiway was via the "S" weave technique required for most taildraggers since my forward view was obscured by the nose and Sean (who was doing the "driving") could see even less in the back! The gun barrel seen on the starboard side of the nose was a reminder that Texans were armed and used for fighter as well as basic flying training. They could of course also be used in anger against an enemy. Texans were generally equipped with three guns, one in each wing and one in the nose, the latter accompanied by propeller interrupter gear to avoid shooting the prop. Some were fitted with a gun in rear cockpit for defence. There were also wing hard-points for rockets or 250 lb bombs. This particular plane was originally a naval SNJ built in 1945 used as an instrument trainer at Pensacola. Sold in the late 1950s, it was converted to the USAAF specification by replacing the naval castoring tailwheel with a steerable one. We passed several hangars along the taxiway housing airport services and businesses. Sean pointed out one relating to aircraft restoration and Warbird flight training containing another Texan, two P51 Mustangs and a P38 Lightning. The Texan and P51s are used for taildragger training for those wealthy enough to have their own Warbird(s) and learning to fly them. Reaching the hold for runway 15 Sean carried out magneto checks and propeller pitch cycling. We had to wait for a small business jet to land and then it was our turn. Sean (understandably) carried out the take-off and initial climb himself, but after attaining a reasonable height he uttered the words "you have control" and the aircraft was mine. I was given a bearing and airspeed to hold and managed to get the feel of the controls quite quickly. I found the plane to be very stable but with light and very responsive aileron and elevator controls. A millimeter or two of movement was enough to change or keep the angle of pitch or roll. Since simming is by default in two dimensions it lacks the benefits of peripheral view and I generally fly with an augmented minipanel, making good use of the AI and VSI. The absence of these instruments was a little daunting at first but I soon learned to make use of visual cues to maintain the required pitch and lateral position, supplemented by frequent scans of the airspeed indicator and the altimeter. We climbed at about 160 kts up to 7,500 feet making several heading changes to get us to the designated patch of sky where the aerobatics would take place. It was a great feeling, this flying for real, and I enjoyed the challenge of simply maintaining altitude speed and direction - no autopilot here! Of course I had no idea where we were in relation to the airport - my concentration was entirely focused on keeping the plane where Sean told me, but he knew exactly where we were and when we arrived, it was show time... There were eleven manoeuvres to perform and due to the Texan's carburation, all had start with a climb so as to be under positive "G", necessitating an initial dive to attain the required manoeuvre entry speed. In each case, Sean performed the manoeuvre first, narrating the required actions and key points, then I had a go. First up was the "wing-over". This has an entry speed of 170 kt to give the necessary speed to fly a climbing left turn which is held until the aircraft rolls inverted then falls away, when you pull back and straighten up, facing the way you came. My first attempt at this was rather poor, because although Sean had demonstrated very positive climb, mine wasn't as good. I was able to repeat the wing-over and made a much better job of it second time around. Next was the aileron roll, which when well performed properly makes the aircraft rotate about its longitudinal axis through the nose and tail. Entry airspeed this time was 175 kt. Entering a 30° climb the roll is started with a slight nose up and full aileron whilst holding the elevators steady. At my first attempt I wasn't quick enough with the aileron pressure and the roll was very scruffy, losing height and too slow. Sean reminded me that I couldn't "break" the aircraft with a swift roll so I tried again and although better this time, I was still far below display standard! The loop - everybody's idea of aerobatics. This has an entry speed of 185 kt which when attained required me to pull the stick back as far as it will go. The Texan responded immediately, pulling 3G as we went over the top. The speed and the G force was quite exhilarating but not so much as to cause a blackout, so I was able to see the whole loop by tilting my head back to look for the horizon as we went over the top. Sean had to remind me to keep the stick back the whole way round until we neared the point for levelling off. The barrel roll is somewhat easier to perform than the aileron roll and is impressive to see and to experience. Entry speed is 170 kt as for the aileron roll, when the stick is pulled back (but not as far as for the loop) and aileron applied. The aircraft then describes the path of a corkscrew on its side. This manoeuvre includes elements of both loop and roll since you become inverted at the top of the roll but have also risen in altitude from the start. You can vary the diameter of the barrel roll by the amount of aileron fed. On my first attempt the balance of elevator and aileron was not good, but on the second go I managed to describe a very large and slow barrel, which was very satisfying to complete. One of the most famous executions of a variant of this manoeuvre was by Tex Johnston in 1955 when he did a chandelle in the Boeing 707 prototype on its first demonstration flight. When challenged about this by Boeing bosses after the flight Tex dryly remarked to the effect that the 707 didn't mind at what attitude it flew, as long as it remained in positive G. See the video of this flight here. Alex Henshaw added a barrel roll to his production flight testing of Avro Lancasters from the Castle Bromwich factory during WWII. You can read about this in his book Sigh For A Merlin. Alex later recorded that he always worried about doing this "in case it looked untidy from the ground!" The immelmann turn followed and Sean recounted the history of this manoeuvre which was originated in WW I by the German fighter pilot Max Immelmann as a means of creating two attacks on an opponent in one move - from the rear during the dive entry then head-to-head after the turn. The original Immelmann was more of sharp turn at the top of a steep climb whereas the aerobatic Immelmann is actually a half-loop followed by a roll off the top. The loop entry was the same as before and the trick is to watch for the horizon so that you start the roll to the left as you become horizontally inverted at the top of the loop. All the rolls I did were to the left as the torque-roll effect of the propeller makes them faster and easier. An inverse looping manoeuvre, the split-s, starts with a shallow climb to reduce airspeed to 90 kt before rolling inverted and pulling down and round the loop. This is simpler to perform than the standard loop and on the way down you get a much greater impression of heading towards the ground. The "Cuban-eight" followed; a purely aerobatic manoeuvre conceived appropriately enough, by a Cuban aviator. Once again it's a dive to 185 kt then over the loop but holding it until you are still inverted but at 45° to the horizon at which point a swift roll to the left brings you upright in a 45° dive. Remaining in the dive until you attain 185 kt again enables you to repeat the manoeuvre in the opposite direction, thus creating the full "Cuban 8" - a figure 8 on its side in the sky. Sadly, we didn't have any display smoke so I couldn't see the effects of my manoeuvre. The opposite manoeuvre is the reverse Cuban-eight. This starts with a dive to 170 kt then a 45° climb to 100 kt at which point a 180° roll is executed followed by a pull around an inverse loop and back up into a 45° climb to repeat the manoeuvre. The "hesitation roll" is very difficult to perform properly as it requires precision stick movement and timing. This roll is initiated in the same way as the aileron roll with a 170 kt start and 30° climb but instead of a continuous and smooth rotation has a series of 2, 4 or 8 "stops" in the roll. Sean demonstrated the 4 point roll which I was to copy. I found that each stick movement for aileron has to be very quick with a sharp stop at the required angle, in the case of a left hand roll - 9 o'clock, 6 o'clock, 3 o'clock, 12 o'clock. The penultimate manoeuvre was the cloverleaf which combines components of a loop and a barrel roll. The full cloverleaf is comprised of one manoeuvre carried out four times in a continuous movement. Following a dive for 185 kt airspeed I pulled the aircraft up to a vertical climb then executed a left quarter barrel roll which turned the plane through 90° then I pulled through an inverted loop whilst maintaining the left aileron such that on level-out I was facing north from an original west direction. Repeated three times the plane describes the shape of a 4-leaf clover as seen from the ground. Of course display smoke helps here. My first attempt at this manoeuvre illustrates how a moment's confusion in an aircraft can bring potential disaster. Sean had demonstrated the movement (flawlessly as usual) and as we began the climb he gave me a prompt to begin the second sequence by saying the word "right". Now I knew that I was to make all rolls to the left but the combination of my anticipation and his word "right" cause me to start a roll to the right. Sean immediately took control again to avert an inverted stall. I was able to have another go and was more successful. I can't help thinking that having been denied an inverted stall several times during the flight, perhaps Sean should have let me complete one to see what it's really like! The victory or slow roll is an elongated version of the aileron roll at a reduced rolling rate. I set up an entry speed of 170 kt, climbed to 45° then used a small amount of aileron to create the slow roll. If I can quote Alex Henshaw again; his commentary on performing slow rolls in a Spitfire states that during a left hand roll right rudder should be used when approaching the 9 o'clock position and left rudder when approaching the 3 o'clock position to keep the tail in line; centralising the rudder when approaching the 6 o'clock and 12 o'clock positions. I have tried this since in the sim and the touch required needs to be very deft indeed - such as only the likes of Alex Henshaw could deliver properly. It was now time to head back and the amount of cloud had grown significantly during our aerobatics session forming a fragmented blanket beneath us. Since the fight was under VFR conditions we had to descend to fly under the cloud base and Sean directed me to a usefully sized hole which I navigated towards like a target. During the descent Sean had been talking to a fellow pilot in the Texan we'd seen in the hangar on our taxi out. Levelling out just under the cloud base at 2000 feet I could feel the turbulence effect on the aircraft and see occasional spits of rain on the canopy. The other Texan closed in on us from above, appearing a little higher than us at our 7 o'clock position. He offered to do some formation flying with us which Sean accepted, then banked underneath us to our 5 o'clock position and inched slowly forward to our 2 o'clock. I just kept our Texan straight and level and enjoyed the chance to fly in formation "for real". The other plane then moved in front of us to "line astern" which the pilot held for a few seconds before he moved to our 10 o'clock. Finally the Texan left us in a classic peel off to port. This last bit had been an unexpected and fantastic experience. Having done some formation flying with AI aircraft in the sim I know how difficult it is to maintain bearing, altitude and distance from the other plane. This pilot was obviously well practised in this skill. We continued on our way back to the airport and the clouds thinned a little as we got closer to home. Sean had one more trick to demonstrate - a break-to-land. Having called this in to ATC he took the controls and lined up on runway 24 (different to the one we took off from) which we could just see in the distance. He then descended to 1000 feet. There was a high-wing Cessna on final below us which touched down as we crossed the threshold at our 1000 foot altitude. Sean then peeled the Texan into a descending starboard turn, lowering the gear and the flaps on the way down. As we came around the circle on a curving approach Sean kept the line of the curve so that as we straightened up we were lined up perfectly on the runway which we could no longer see. The touchdown was suitably gentle and as Sean taxied us back to the hangar, two thoughts prevailed in my mind - this had been a fantastic experience and it was all on video for me to re-live again and again! I had another browse around the museum while I waited for the video to be copied to DVD. The drive back to the villa was significantly uninspiring.... For anyone going to (or living in) Florida this flight is an experience I would thoroughly recommend and worth saving up for. Although you can get a similar type of flight in the UK, the warm and clear Floridian skies offer much more chance of avoiding a weather related postponement, the whole ambience is certainly more relaxed than in the UK and, I bet you won't get to fly a Texan. If this has whetted your appetite for aerobatic simming, there is a good web site that describes the manoeuvres and here's a freeware Texan for which you can find a very large range of repaints. Happy flying! Derek Swanson derek.swanson10@virgin.net