Monday, May 08, 2006

The Dreaded Annual - Part 2

There are many maintenance facilities around the country that can do annual inspections on airplanes. Living in Chicago, I'm fortunate to have access to some of the best in the country. However, being the best shop working on a Piper or a Cessna doesn't qualify you to be the best shop to work on a Mooney.

All Mooney airplanes are highly-complex and fast. Al Mooney, like Burt Rutan, worked at various traditional aircraft manufactures. These guys wanted to push the envelop and make a good plane better and the traditional companies balked at this. Al didn't subscribe to the belief that "it's good enough" was indeed good enough...He wanted to build the best (Faster, Higher, Fuel-Efficient). The M20K TSE252 was the ultimate realization of Al's goal. The Ovation and others that came after it were not the fuel-efficient fast machine Al wanted. Al believed a perfect airplane is a balance of speed, capacity, range and fuel efficiency. The 252 has it in spades!

The M20K 231 was the first Turbo Mooney ever built. Mooney Corporation was directly competing with Cessna and they had the P210. The 231 was fast (231 MPH) and efficient, but it had its limitations. It is very easy to over temp a 231 engine basically destroying it. Most 231's on the market, and there are many, have had top overhauls and turbo replacements. This is the tell, tell story of the 231.

The M20K TSE252 was the natural evolution of the 231. Mooney Corporation had several years of experience building, flying, and warranty repairing the 231. They knew they could do better. They went to Continental, the manufacturer of the TSIO-360 engine, and asked them to improve it. They went to their engineers and told them to fix the heat problems -- and make it the fastest production airplane ever!

Here's what they did...
(quote from Mooney Aircraft Pilots Association -MAPA)

"Engine cooling was attacked in two ways. First, larger cooling air inlets were cut into the front of the cowl. Second, the outlet area was increased at the bottom of the cowl for all this added cooling airflow to exit. The dual, horribly inefficient cowl flaps on the 231 were replaced with a single, infinitely adjustable electric cowl flap on the 252. These two changes (inlet area and cowl flap) resulted in a lot more cooling air entering and exiting the cowling. An added benefit was a slight reduction in cooling air drag, as a result of the larger, more efficient cowl flap on the 252. These changes worked wonders. The 252 is one of the coolest running turbocharged airplanes ever.

The next big change with the engine installation was a redesign of the 231’s primary induction system. The 231 has a complex and relatively inefficient duct arrangement mounted on the copilot side of the engine. From flight testing, we knew it was inefficient, choking air being delivered to the compressor. Second, it was prone to allowing ice particles to enter the inlet duct and collect on the face of the induction air filter. A side mounted NACA duct and filter can arrangement was designed and tested that was non-icing and that delivered lots of induction air to the compressor. What a great change! The TSIO-360 in the Mooney now had plenty of induction air to breath and use for combustion."

Wow what a difference! You can climb a 252 at full power to 28,000 ft without worrying about the engine over temping, you can takeoff at full power thanks to the automatic waste gate, you can truly achieve a "real world" 252 MPH out of the same 210 horsepower and you can easily make it to TBO as long as the engine is maintained properly.

"Maintained Properly" was my queue to find the right place to do the annual. I know my way around airplanes, but I wanted the best of the best to check her out.

How do you find the best? In a word -- "Research." So that's what I did. There are approximately 50 Mooney Service Centers in the USA including Mooney Corporation. Out of the 50, however, there are only six not counting Mooney Corp that routinely surface as the experts:
The next step is to narrow the list down to one. How did I do this? I asked the people that know Mooney's...starting with Mooney Corporation. I found out that the CEO at Mooney, Gretchen Jahn, was a big time air racer. She competed quite often, but never won until she started flying an Ovation. Turns out that Gretchen would go to Midwest Mooney to prepare her airplane for racing. This was impressive considering she's the CEO of Mooney -- you know the people that build them!

The next step in the quest to find the right shop was during our annual trek to EAA Airventure Oshkosh. I met with everyone that owned a Mooney I could find and spent a lot of time with the Mooney pilot associations (MAPA & MOA). Amazing enough, everyone seemed to recommended Kevin Surrell at Midwest Mooney as being the best in the business. In fact, MAPA actually had a newly STD'ed airplane in front of their booth that had the "Screaming Eagle" conversion designed by Midwest Mooney.

The final decision came down to the Mooney Corporation announcement. They announced they were going to start making an Ovation III. What makes a III different than a II? The Midwest Mooney STC! Wow, what a complement.

Kevin and company did an awesome job creating the STC, being recommended by many as the best and they were in Southern Illinois -- The decision was made...Our first annual will be at Midwest Mooney!