Thursday, April 22, 2010

Advanced Spin Training with Rich Stowell



The need for training

The weekend of April 17-18 2010, I finally did it. Went ahead to get some advanced spin training, so that I could practice all the aerobatic maneuvers with confidence. Especially when you are learning to do new maneuvers, there’s always a chance that they end up in an “interesting” position. For instance an overly aggressive push and roll input to fix a hammerhead (stall turn for those used to Brit terminology) at the top of the vertical climb puts the controls in a classic accelerated flat inverted spin entry position. (Full power, low speed, full rudder, forward stick and opposite aileron). I had done inverted spins in the Christen Eagle but that was from power at idle, with known yaw direction and known recovery rudder. I was not a 100% sure that I would recognize an inverted spin and do the correct recovery when confronted with an unexpected spin.

The choice of school/instructor

I had a few choices in the US where I could do this training. I thought I could go to Debbie Rihn-Harvey’s school near Houston and do it in their Pitts S-2B. Since my sister lived there, this was an attractive option. I could visit with sis, stay for free and borrow her beater car to go to and fro from the airport (leaving more money for the flying!). Debbie had a great reputation and was a National Champion and their website advertised training of this kind. However, their Pitts had been in for repair and was not available for over 3 months.

The other option was Rich Stowell in Santa Paula, CA. Rochelle, a member of the group that co-owned the Christen Eagle, was a student of Rich’s and had done a lot of her flying with CP Aviation. Rich works out of CP Aviation which is the FBO at SZP (Santa Paula airport). Rochelle had been recommending working with Rich or Judy Phelps as instructors for this sort of thing. After not getting a satisfactory reply from calls to Harvey Aviation I decided that it worth the additional investment in a hotel room and car rental to just go there.

It helped that Rich was nationally known as a really good instructor. He specializes in upset, spin and aerobatic training and has been known to do it at least since 1988. (There is a “Flying Magazine” article on a CP Aviation wall featuring him from that date). He has written at least two books (Emergency Maneuver Training & Light Airplane Spin,Stall/Spin Awareness) about spinning and upset training. He has a bunch of videos about flying aerobatic maneuvers and gives an accessible yet scholarly treatment to the subject.

Rich has seminars that he instructs in all over the country but every time he has been up in the Pacific Northwest I haven’t been able to attend. So I got a weekend slot with him and headed to Santa Paula. I flew into LAX on a Friday, rented a car and was at the quaint Santa Paula Inn B &B in a couple of hours.

Arrival and preparation

SZP airport is real interesting. It is walking distance from downtown Santa Paula, and is a hub of activity. People can come and watch airplanes and the overall feel is much more relaxed than the fenced off areas that most airports have become. I think this is more secure than fences, since everyone seemed to know each other and care about "their" airport.

I showed up at 8:30 am for a 9 am appointment at CP Aviation. CP stands for "Clay Phelps", who is the owner/A&P/IA of the school. According to the historic photographs I perused, Clay's father Robert Phelps operated a flying school at Santa Paula for the US Army Air Force in WWII. Clay's wife Judy is an aerobatic instructor of note.

Rich arrived at 9 am, and looks exactly like his pictures. I was his only student for the day, which was nice since I got to hang out with him all day.

We went to the back room to brief the flying for the day. In an e-mail exchange with Rich, I had asked for training in spins especially recognizing and recovering from inadvertent spins while doing aerobatics. I told Rich that I wanted to do regular, accelerated, inverted, flat spins so that I had seen them all and could recognize them and do something other than freeze or flail on the controls when I got into one. Regular spins are entered with the power off and at low speeds, but in aerobatics one can enter them with full power and at higher speeds. This can cause a high rate of rotation and since they can be entered inadvertently rather than deliberately can cause a high rate of rotation inside the pilot's brain - leaving him dazed and confused!

Rich had asked me to plan for 3 flights on Saturday (9am-11am, 12 - 2pm, 2pm -4pm). I had a late flight back home on Sunday - so we had the whole day to do further flights if we needed to. I also had in mind some coaching for competition figures from Rich.

I had asked to fly CP Aviation's Pitts S-2B. The Eagle is very pitch sensitive with two persons on board, and is easily loaded beyond it's aft CG, especially with my weight in the rear seat. The Pitts S-2B is similar to the Eagle in flying qualities but has a larger engine with more horsepower. It has a six cylinder 260 hp Lycoming IO-540 versus the 200 hp Lycoming IO-360 of the Eagle. This allows it to carry more weight and gives it a wider CG envelope.

Rich asked me what I wanted to get accomplished and I told him I needed to get comfortable with being in unusual situations - which included spins of all kinds so I would not be so tentative in flying maneuvers that took me to the edge of control especially if they were botched. I told him I was doing hammerheads early because I did not want to fall into an inverted spin. I had done both upright and inverted spins - but these were deliberate spins that I had set up. Recovering from them did not give me confidence that I would recover from spins which could go flat, be inverted when I was expecting them to be upright and vice versa. I had reasoned that if I saw enough spins of different kinds I would be able to (a) recover correctly from them and (b) practice them solo in the Eagle to keep current.

Rich's briefing wasn't very long, or at least it didn't seem that long to me! His experience showed in that what I thought was a short briefing prepared me very well. He has a metal model that I have seen in many of his videos that illustrated aileron, elevator and rudder positions in various maneuvers. This was great training aid, since it allowed one to visualize what control positions corresponded to control inputs in entering and exiting maneuvers. It also showed how my mental model of what happens inverted was a little incorrect!

We agreed that we would do three flights that day (Saturday) and would keep the schedule open on the next day (Sunday) to see if we needed a couple of more flights.

The Pitts S2B

I then started preparing for the flight and Rich went ahead to prepare the Pitts S2B for me, including the parachute. I hopped into the rear seat. The Pitts has no floor, so getting in and out is harder than in the Eagle. One has to put one foot on the seat, slide the feet on the rails taking care not to land on the lexan floor and lower ones butt to the seat. In the meantime, the canopy has to be held so that it is not carried away by the wind! The Eagle canopy is solid, whereas the Pitts canopy is very delicate. In the Eagle the engine can be started with the canopy open. Rich said that so many people were losing S2B canopies (which can cost $6000 a pop) that insurance companies do not cover canopy loss on S2B anymore! Even the canopy lock is just a pair of plastic slots into which the canopy is pushed till it clicks, as opposed to the solid lock and pin of the Eagle!

Overall I was surprised by how rough and sparse the S2B cockpit was. I assumed that since the S2B is factory built and was certified under the aerobatic category, it would be more refined than the experimental category Christen Eagle. Wrong assumption! For instance, the prop control on the S2B is a metal lever that has to be teased back when it is at the right angle using the metal tab attached to the lever. Hard to get precise RPM control with that! The trim tab is a plastic lever that points to the floor!

The Christen Eagle seems much more of a factory built than the S2B and it was built around the same time as the factory built S2A. It is surprising that the S2B wasn't built using the Christen Eagle's cockpit arrangement since by the time it was in production Frank Christensen owned both the Christen and Pitts factories.

Jumping ahead, how was the Pitts S2B compared to the Eagle to fly? Pretty much the same performance wise with two people on board and the higher temperatures at Santa Paula as compared to the Eagle with just me on board and in the cooler temperatures in Seattle. The feel of the Pitts was more "solid" and the Eagle seemed like a lighter aircraft overall. The control forces were smaller in the Eagle all round, though in the heat of the moment they didn't seem that much more in the S2B! Budd Davisson's article on the Eagle has a comparison with the Pitts and I pretty much agree with everything I said. Though for overall comfort I would choose the Eagle any day.

Hurry up and wait!

Rich completed the briefing and strapped in in the front. However after start up I couldn't hear him on the intercom. We thought it might be my headset, but even after swapping headsets he couldn't hear me on the intercom. Having a fully functioning intercom so that I could hear Rich's instructions while I was in an inverted flat spin was kind of important! So we had to shut down and see what could be done about it. Rich called the owner - I took the opportunity to have lunch while waiting. Having planned the extra day immediately started looking like a very good idea. Rich wanted to make sure I could fly the Pitts but was also thinking that the Decathlon would be a back up if things didn't work out. My attitude was that things like this happen in aviation and are instrumental in building character!

The first sortie & SOP at SZP

After a couple of hours, Clay Phelps was able to wire the intercom so that it worked. He is an A &P and found that the problem was that the ground of the intercom plug was not connected. An external ground wire to the headset plug did the trick and we were ready to fly.

Santa Paula is a different kind of airport as I have alluded to before. One unique thing is that aircraft are identified by type and color rather than by call sign. So we were the "blue and yellow Pitts" rather than "Pitts Eight Zero Alpha Sierra". The traffic pattern is at 850 feet and has specific landmarks it is flown by. Close by on the east side is a pretty big mountain and all patterns are flown on the mountain side of the airport.

The aerobatic area is north of the airport between the cities of Santa Paula and Filmore, with the highway between the two conveniently bisecting the area into West and East practice areas.

Rich had me do the takeoff and get used to the Pitts handling, asking me to do a couple of Dutch rolls. Once in the aerobatic area we did some upright spins to the left and the right. Rich has a very calm, unhurried way of instructing. He used my name before asking me to do something - which did get my attention. Things were happening fast, but his instructions always seemed timely but unhurried!

We then went into aggravated spins - putting out spin aileron & forward stick before rudder during the spin. The two things that I took away from the spins was

  1. Wiggle my toes (so that I was sensitive to the rudder)
  2. The spin stops when I could point the aircraft's nose to a point and make it go towards it (no yaw)
We practiced PARE & Begg's recoveries. PARE is an abbreviation for "Power (off), Ailerons (neutral), Rudder (opposite yaw), Elevator (towards neutral)" and is something that Rich has popularized (and trademarked). Begg's recoveries are named for Gene Begg's whose book "Spins in the Pitts Special" specified how a Pitts recovers from any type of spin by letting go of the controls, power off and yaw (rudder) opposite to the spin yaw direction. The way one judges what opposite yaw is to "catch up with the world with your rudder" , subject to the world being viewed by sighting over the cowling between the wings of the Pitts (in an inverted spin if the world is not being viewed over the cowling the direction of turn will be judged incorrectly). The Beggs recovery works just as well for the Eagle.

Flat spins for the first time
Now it was time for flat spins. These were entered like a regular upright spin but as the first turn was completed the power was brought smoothly up at least half way. That caused the world to spin around way faster! I did the PARE recovery first. Normally with power off and opposite rudder the Eagle/Pitts is already coming out of a spin, and it takes about a quarter turn to recover. Doing competition spins you have to work hard so that the spin doesn't stop before the required points. Not so in a flat spin. In a flat spin it took about a full turn to recover. Rich's dictum of the aircraft being out of a spin only when going towards a point on the ground is invaluable here so that one doesn't remove anti-spin inputs prematurely.

The Beggs recovery was pretty much the same, though I was surprised by the" rising out of the seat" feeling which made me instinctively grab the stick as the airplane pitched down to recover itself from the spin after anti-spin yaw was applied. I also found out how hard it is to just let go of everything, and understand better now why people have grabbed on to the controls and never let go! Practicing this with Rich has definitely made it much more likely that I will use this recovery method with fouling it up. We did flats spins to the left and the right before moving on to the "piece de resistance" - post stall gyrations and hammerspins!

Hammerspins
One of the maneuvers that was in the IAC Sportsman class category competition that was not in Primary category competition was the hammerhead or stall turn. I was a little wary of this maneuver since it was a low speed maneuver in which the rudder was the primary control input. There was always the danger of falling into a spin or leaving it late and falling into a tailslide. This lack of confidence had me doing the yaw turn way too early and tentatively. I had mentioned this to Rich and serendipitously he had just finished filming a video about hammerspins for the new IAC "In the Loop" newsletter. In fact the mount for the video camera was still on Eight Zero Alpha Sierra.

The video Rich shot is below, and is well worth a look see.


Rich had me do the first maneuver to demonstrate that the airplane is actually trying to do the right thing, and that it doesn't just fall into a flat spin but gives ample warning even under extreme conditions. He had me set up the hammerhead and at the top give full left rudder, full right aileron and then full back stick. I had to hold these control inputs till the aircraft entered a recognizable left flat spin. He had warned me that there would be three warnings or post-stall gyrations before a flat spin would happen.

I did the entry just as is shown in the video, and the aircraft did 3 yee-ha maneuvers pitching over, pitching level, pitching over, pitching level, pitching over and entering a flat spin. I had the controls in the really unnatural pro-spin direction all the time. Then I recovered from the spin using PARE. It actually isn't as violent feeling as it looks and was a smooth maneuver.
We then did the maneuver and recovered from the flat spin using the Beggs recovery.

It was now time to head back for the landing. Since I had never landed a Pitts before, Rich wanted me to have enough spare capacity to land the airplane. The runway at SZP is only about 2500 ft long and it has houses close to the fence under the approach end of 22 where we were landing. The S2B stalls around 80 mph, whereas the Eagle stalls at 60 mph, so we maintained 100 mph all the way around, reducing to 90 mph over the fence. It lands much like the Eagle, and is equally blind!

Sortie two
After a brief debrief (heh heh) and some coffee we launched for our second sortie of the day. This time we concentrated on competition maneuvers - Rich had me do left and right competition spins so that I could internalize what controls to put in when and in what order. He also coached me on my hammerheads - making sure I understood what truly vertical was and the sequence of controls on the turn around at the top of the hammerhead. One other maneuver we practiced was getting into a the aggravated hammerspin and recovering way before it turned into a flat spin using the Beggs method. This increased my confidence in doing the hammerhead turn thousandfold. Another landing followed, and I was done for the day.

Day two: Introduction to the Decathlon, Inverted spins and inverted turns
When I arrived on day two I expected to fly the Pitts again. But found that there was a more serious problem with the intercom system. Scott, the owner of the Pitts on leaseback to CP Aviation, had the Pitts intercom out and showed me where there were burn marks on the circuit board. This was going to take more time that I had to fix.

Rich in the meantime had brought out CP Aviation's Bellanca 8KCAB Decathlon N5035N or "blue and white Decathlon" in SZP vernacular. 5035N has a 150 hp engine and fixed pitch prop. I was happy to fly the Decathlon just to see how I would do doing aerobatics in an aircraft without quite the power, feel and control authority of the Eagle/Pitts. I have flown Citabrias quite a bit, so the cockpit and controls were familiar. The visibility out the front was certainly a lot better than the Eagle/Pitts!


Rich started me out flying dutch rolls and aileron rolls so that I could get a feel for the aircraft. The Decathlon has a symmetric wing, so it doesn't need quite the nose up attitude that is needed when inverted in a Citabria. It was still quite a bit more than the Eagle/Pitts. Control forces were certainly heavier!

Then Rich had me go through being comfortable inverted in the Decathlon. He had me try some turns this way. The mantra being
  1. push the rudder in the direction you want to go and
  2. lift a wing by stick into the side you want to lift (the opposite of when one is upright).
We then did some 60 degree steep turns inverted. I had to put in lots more forward stick to turn (since elevator makes the airplane turn once banked, and one needed forward stick to get the turn going). In the Decathlon that much forward stick means that the stick disappears under the panel! That was kind of awkward. It was also weird to feel like one was on the outside of the turn being thrown out rather than on the inside of the turn being pulled in while upright.

It was then on to inverted spins entered from inverted flight (we seemed to spend more time inverted than upright in this sortie!) with brisk rudder application and forward stick for entry. In the Decathlon, the Beggs recovery does not work. In fact the stick can go hard forward and stay there! There is 10-15 lb force required to pull it back towards neutral for recovery. We did both left and right inverted spins and recoveries. Now it was time to land, and I had to be reminded that the sight picture would be lower than my Eagle or the Pitts because the Decathlon does not have quite the same sink rate as those types!

What did I get out of this?
On the whole this was a very educational and fun 3 sorties. I am very confident that if I fall into a spin of any kind I will be able to do the right things to recover. As far as I am concerned the most important teaching that I got from Rich was "forget about the drama going on outside the airplane, just do the process and you will be fine". I also realized that I should get recurrent training like because as someone on the Acro group said "Hitting a maneuver like the hammer perfectly every time doesn't really expand the repertoire, but poking the Pitts /Eagle with a sharp stick (under expert guidance) really teaches a lot!"

1 comment:

Gp Capt Kapil Bhargava (Retd) said...

Absolutely fascinating description, exercises and the writing! Well done Anandeep. This made me salivate for flying, which sadly is no longer possible for me. I never got anywhere near this proficiency even during my test pilot training in UK, That was fun of a different kind,54 years ago. Let us see more of your adventures, preferably with an alert to my email address.

With all good wishes, and thanks for sharing with us the joy of flying.

Kapil Bhargava
Bangalore, India .