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Monday, January 5, 2009

Engine Choice

Engine choice is a major decision as part of building an airplane.  Its really one of the most expensive and most important parts of the finished airplane.  For RV-7's the engine pretty much has to be the Lycoming style 4 cylinder engine.  There are many options that the builder must determine though starting with Horsepower..   ;-)   Also, ignition type, aspiration type, injection, sump type, etc..    I won't go into all the details, but I chose to buy new, non-certified.  Basically built the same as certified, but less government mandated paperwork, so it is less expensive.   Realistically there probably isn't any safety difference either, and the engine is warranted for 3 years which isn't typically the case with a new certified Lycoming.. 

The engine I ordered is about the highest end engine for the RV, outside of the 390's or the 200 hp angle valved engines.   Its a high end, high horsepower (195 hp), mid sized (360 sized) engine..  With this engine and prop combination that I am going with, as quoted by Larry Vetterman, I won't be "tail end Charlie"...

I chose to go through Aero Sport Power up in Canada.. They go a great job and have many good recommendations..  Plus I met the owners Bart and Sue both at Arlington fly in and Oshkosh fly in last summer..

A final thing to consider is fuel..  Avgas is 100LL and there may be changes to this over the next few years..  The engine I bought has low compression cylinders which allow for lower octane fuel such as premium auto fuel.. (but it can't use ethanol)..   So with this engine I should be safe with what ever future fuel is used for aviation engines..

Below are the Specs:

Aero Sport Power Ltd. New IO-375 (195 HP) Horizontal Induction Engine Includes:

Superior Cylinders with standard 8.0 to 1 compression ratio, One Slick Magneto and Harness with Light speed Plasma II + Crank Triggered Electronic Ignition, Spark Plugs, Sky-Tec Light Weight Inline Starter, Plane Power 60 Amp Alternator, Precision Silver Hawk Fuel Injection, Fuel Pump, Camshaft and Lifters, Superior Cold Air Horizontal Induction Sump, Connecting Rods, ECI Crankshaft, Dynafocal Type 1 Crankcase, Ring Gear, Inner Cylinder Baffles, Dipstick and Tube, 90 Degree Spin on Oil Filter Adapter and Vacuum Pump Adapter Housing.  Engine to be painted yellow, cylinder black bases and gold alodined fins.  Inverted oil modifications.

Constant Speed (M1S) Outright
Using Superior Components with Roller Lifters

Here is a pic of one of their recent engines..   Mine will be Yellow where this one is Red, plus this one has two mags where mine will have one mag and one lightspeed electric ignition, also mine will be fuel injected.  But in general it will look like this one.

Sunday, January 4, 2009

Tip Up v.s. Slider Canopy

This decision is a tough one that all builders must make.  Luckily, like the landing gear configuration, I don't have to make this decision until I order the fuselage.  I am currently leaning towards:  Tip Up !

Reasons being:
  • Ease of Construction
  • Visibility
  • Visibility
  • Ease of access to Panel
Potential Drawbacks:
  • Less Taxi Ventilation
  • Some think less sexy look.
It seems to be pretty evenly distributed between what builders decide to go with.  I may change my mind, but really think that the visibility is worth it when you are flying.  On the ground, you can still open the tip up while taxiing, and I still think it looks good tipped up when the plane is sitting there.   The only think I won't get is being able to hang my arm out the window when taxiing.   Well, I think we are going to get Bekah a convertible car here pretty soon, so I can get all my hand hanging out done on the road.  Then I won't feel the need to hang it out of the airplane.  ;-)

The tip up is designed so that the back of the panel becomes completely exposed when it is up.  Providing great access to work on instruments...  I could build a modular panel to make it easier to work on the panel of a slider, but still more work and even such isn't as easy as the tip up.

Now I have only flown in a Tip Up RV.  The visibility was unbelievable, it felt like you were sitting on top of the engine and nothing else was there.   I would like to fly in a slider to gauge the difference that the front roll bar and post make, but I am thinking it will definitely distract at first.  I  am sure you get used to it and never see it, but still uninterrupted visibility sounds pretty good to me.

The only thing I want to look further into is how builders seal the front edge of the tip up, I understand if not careful, water can get in.  I live in Seattle and will be flying in the rain, need to avoid water entry as much as possible.

All in All, for now, Tip Up it is.

Tip up Pic:

Slider Pic:

Saturday, January 3, 2009

Tail Dragger vs. Tricycle

I don't have my tail dragger endorsement at this time, but am about 100% confident that I am going to build a Straight RV-7 meaning it will be a tail dragger.  The -7A is the tricycle gear meaning it has a nose wheel up front.  While tricycle gear planes are easier to land and maneuver on the ground I don't think they look nearly as good.

For me I like the classic look of the tail dragger and will get my endorsement and practice in a tail dragger before I get to the point where I have to make my final decision.  You don't need to make a final decision until you order the fuselage.  I am pretty sure I will enjoy flying the tail dragger even though it will be a bit more challenging to land and maneuver.

For those who don't know, the center of gravity on a tail dragger is behind the front main wheels which means while on the ground, the body of the aircraft can get away from you either left or right and flip around towards the front.  This is called a ground loop and can be pretty dangerous.  To avoid this, the pilot has to use a lot of rudder to keep the plane straight while landing and taxiing. 

A tricycle gear airplane, the center of gravity is in front of the two main wheels so the plane naturally wants to roll nose first, so a ground loop is not common if even possible on a nose wheel airplane.

But I have spoken with lots of tail wheel pilots and they love the challenge and reward that comes with flying tail wheel planes.   Also, they are a few MPH faster since you don't have the nose wheel sticking out.  

Plus they just look very classic and way cool.

Also in particular on an RV, the wing walk is closer to the ground on a tail wheel version, so you don't need to install steps on the fuselage to allow passengers easier access to the wing walk.

Friday, January 2, 2009

Why Build an RV-7 ?

Over the last years I have been trying to decide which airplane to build. It's a big decision and once you make it you are kind of stuck with it for obvious reasons, but boils down to money and time. I had 3 aircraft in mind all with big differences.

The Three were: One of the RV's, a Murphy Rebel Elite, and a Glasair Sportsman 2+2.

This isn't an RV-7 Commercial, but here is why I chose the RVs.. They are common, proven, lots of builder assistance available (even though maybe harder to build than others), proven track record of the company. Relatively inexpensive. Fast, fully aerobatic, great visibility.

The other two planes I was interested in were more of the bush plane nature where the RV is more of the sport plane. Its faster and more aerobatic.. Great for cross country. But just the same, I really like the idea of a bush plane. The sportsman is 2+2 meaning 2 larger people and 2 smaller people can fit in the plane, great set up. If just Bekah and I are traveling we could take about 300 pounds of luggage in this plane, she would have liked that. The Rebel can fit 3 people, but it in particular is pretty darn slow, more along the lines of Cessna speeds. Big tires and or floats someday on both of them would allow for those planes to go anywhere. Also, high wings on them would keep me out of rain and/or provide some shade if necessary on a hot day.

The Sportsman is expensive and lots of composit, I really wanted to stay with aluminum as much as possible. The rebel was good, just not a super beautiful plane. So all in all for many more reasons than I can list here I finally chose the RV. It is damn good looking, you will see.

Now what RV to build..

Aerobatics? YES ! of course, why would you ever want a plane that you couldn't turn over.. So that excludes the RV-10 even though it seats 4.. Plus it is much more expensive and more difficult to build as a slow build. The 10 is really cool, but too big for me to handle for a first homebuilt project.. (oh yes, I think there will be more)

For me I definitely wanted a slow build airplane. All manufacturers offer an option for a somewhat prebuilt wing and fuselage that speeds up the building process. These are pre-assembled in the Philippines..

My airplane is going to be 100% built in the USA..

OK then the -7 or the -8. The -8 is tandem seating and looks good, and is great for aerobatics and maybe even a bit faster than the -7. Both seats have great visibility both forward and back. In an RV-8 you can turn around and almost look at the ground immediately behind the airplane. But the passenger would be looking at the back of my head a lot. I still have hair back there, but still, its odd to be talking to the back of someones head. ;-) So with Bekah and others I really want to be able to sit next to them and look at them when we talk in the cockpit. Also, the -7 is a bit easier to balance out from a weight perspective, and has room for larger pieces of luggage.

So the -7 it is. Best of all options. 2 seats is the only drawback, but I have had 4 place airplanes for about 5 years now and that back bench seat is empty most of the time. I am sure I will miss the 3rd and 4th seat sometimes, but the ability to roll the beast will surely make up for it. ;-)

All in all I am going to be very excited about the fast and sexy RV-7 !

Thursday, January 1, 2009

Why Build an Airplane ?

Wow, why build an airplane? Lots of books on this subject and lots of comments on other sites, but the main reason why I want to build an airplane is because I can. I have always wanted to and never really thought it was possible until the last few years. Watching builders put planes together and fly them; seeing the experiences they have during the build and then the final result has really sold me on this.

The US is amongst the best countries in the world, and our laws allow us to do something as amazing as this. I really hope things don't change in this matter as it would be tragic. Lots of other countries allow experimental aircraft as well, and the whole idea is designed so that people can learn about aviation in general allowing for progress and invention that benefits everyone. Once complete, I really won't have many restrictions with this airplane except I can't fly for hire/commercially and I must make sure that all passengers are aware the aircraft is experimental. No problem, I will be proud of that fact !

Money and Time are key, not sure I have enough of either, but if I put it off, then I will always wish I had started several years ago. Now that I have begun, I can't say that.

Aptitude is important, I think mechanical skill and accuracy are key. I have mechanical type skills in excess even though I don't work in a profession that requires them. I am confident that I have the skills and attention to the right kind of details for this job.

Challenge and Perseverance.. In the few months already building, I understand what others have said. This is something not to be taken lightly and must become a lifestyle in order to finish the project. Since the project is a multi-year endeavor there are many things that happen in life between the start and end. Many builders move homes, old jobs, new jobs, some have kids, even partners come and go in some cases. For me, I plan on keeping everything on the right track if possible, and as I move through life always have that plane growing in the background. (although some might argue it is front and center at times. ;-) )

Any aircraft is only as safe as the last person who maintained or "worked" on it. For me, I am able to build a brand new aircraft that is a proven airframe and can trust myself to the maintenance. Other builders like Dan Checkoway talk about avoiding Monkey's with a wrench. "Guys who are paid by the hour to work on your aircraft." I am sure they do good work, but will they be as invested in the result as I am?
(Certified planes require all essential work be completed by a A&P mechanic, aka "monkey with a wrench".  Homebuilt planes can be maintained by their creator.  -That's me ! )

I love flying and the freedom that comes with it ! Forever I will feel like a 16 year old who just got their drivers license. ;-)

Home built airplanes generally exceed certified aircraft in most ways. Aerobatics, Efficiency, Speed, Payload, Looks, etc.. ;-) Especially the RV Series.

Home Built airplanes/Experimental airplanes mean that it was built by an amateur builder, not that the airframe is experimental or unproven. There are thousands of RVs out there flying today.

Other reasons to come...

Places we have been in our RV-7 ! (Blue 2013, Yellow 2014, Green 2015, Purple 2016, Red 2017)