cgrossl

cgrossl

Well Known Member
I really considering building an RV7, but I have some questions and concerns before I decide to dive in. First off, I am a little over halfway through my private pilot training. I should have my certificate in a month or two. I have been building old cars and hot rods for 12 or 13 years and I am a Design Engineer and a wannabe machinist for a small company here in central KY. So, I am very confident that I have the skills needed to build the plane. I also have a 24x24 garage to build it in, so I have workspace. I can also use the big shop at work if I need to.

Anyway, my first question is how much should I budget to do this? I want an RV7 (taildragger) with night VFR capabilities. I want a VFR panel, with a GPS. I don't want IFR capabilities, but I may elect to upgrade later. I am just fine with regular steam gauges on the panel, but from what I have seen so far, a glass panel costs about the same, if not less (correct me if I am wrong on this). I can take care of the upholstrey work and the paintwork. I am thinking of installing a mid time Lycoming engine. An O-320 or 360 would be fine. Even with the smaller 320, the RV will vastly outperform the Cessna that I'm used to flying. The cost estimator on Van's website is saying 50-55k, but it seems to leave out alot of the smaller items that always seem to add up to alot of money when doing a project like this. So, do you think I can build what I want for 50K?

Of the many reasons that I chose the RV7, one was its capabilty for sport aerobatics. This really appealed to me and is something that would like to do, after proper training. I am just anticipating occasional loops, rolls, spins, and maybe a hammerhead stall, not full on aerobatics or extended inverted flight. Under what conditions will you need an inverted kit for the engine? I plan on installing flip flop fuel pickups, but they don't cost much. Do I have to do anything to the fuel caps or vents? What about the fuel pumps? Will a carburetor work for my application, or will I have to go with fuel injection? If I do need an inverted kit and fuel injection for what I want, what are the limits of the regular oiling system and carburetion? What is a good source for Lycoming engine info?

Finally, I know that I am an extremely low time pilot. If I start building now, I would think that I would have somewhere between 100-200 hours by the time the plane was built. I have always had a better than average "feel" for controling vehicles, even at their limits, but have to wonder if the RV7 will be too difficult for me to fly with only 100-200 hours. I am planning on getting my tail wheel endorsement right after I get my PPL.

I would really like to get a ride in an RV before I decide to build. If anyone is reasonably local to Lexington, KY, I would be more than happy to pay for your fuel and time for a ride in an one.
 
Cameron Grossl,

Here are some thoughts from someone who is well into the building of an RV-7. While it is possible to build a perfectly good RV-7 for 50K, I would caution you that it is awfully hard to resist the urge to add nice-to-have items, and soon you are at the $70,000+ point. While you are building, you are reading and learning about all these wonderful things that you can put in your airplane that you can't do to a factory-built plane. They are hard to resist, especially after you have been working on your plane for awhile, and you want it to be the best it can be.

It sounds like gentlemen's aerobatics are a priority for you. You may decide that a mid-time O-320 isn't enough power. Used O-360s aren't as plentiful as the 320s, so maybe you just buy new. A few more thousands dollars there. To fly extended inverted you need fuel injection and inverted oil. A few more thousands. You can get 10 more horsepower with a horizontal sump. Another couple thousand. To get that awesome climb rate, you'll want a constant speed prop. A lot more thousands. On those long cross-countries, sure would be nice to have a wing-leveler. Another couple thousand. I'm not going to even get into avionics!

... Bill
 
Hi Cameron and welcome, you picked an excellent plane to start out with both for building (lots of support and customization options) and flying (any RV files better than most "average" FBO rentals.

55K is just about right on for a plane with an O320 and wood prop, basic instrumentation, and no paint. If you're a good scrounger and aren't prone to making mistakes that would cause you to order a new part, you can build cheaper. If you want a bigger engine, constant speed prop, or a glass panel, the price will start going up from 55K to whatever you can afford.

The thing I would suggest is don't try to make the plane look like what you fly now. If you think you would *ever* like to do lots of cross country travel, aerobatics, or whatever, go ahead and outfit the plane that way in as much as you can afford it. These planes do go fast compared to a Cessna, but after you get used to that speed, you'll want more, don't skimp if you can afford it. Get the 180 hp motor and CS prop now if you can.

I'll have to defer aerobatics questions to the experts. I don't do them.

Don't worry about flying the plane, it will not be difficult, quite the opposite. In fact, you will find that most other planes become difficult to fly. Get some time in a Citabria and you'll find the only problem you have with a tailwheel RV is slowing it down to the proper airspeed for landing. They will slow right down but it will feel wierd to you after having just gone so fast.

I'm getting ready to build my second RV, an RV-7 so I look forward to building right along with you! Best of luck!
 
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50K is definitely do-able. There are lots of guys who've done it for less and plenty who've spent gobs more. It's real easy to get either sucked in or discouraged by all the planes that have every imaginable gadget, but even the most bare bones RV is still one heck of a nice ride. I'm in the finishing stages (kind of) and here's a short list of some compromises I've made:

No lights except wig-wag leading edge lights. Originally I had planned to have a fancy lighting system, but by the time I got to the end realized I don't really feel safe flying single engine at night over a city, and the extra weight and wiring complexity wasn't worth the trouble. Keep in mind that night flight requires not only external lights, but also lights for instruments and interior. By the way, the only reason I have the wig-wags is because back when I built the wings I cut holes for them. RV building lesson number one: You can't undrill a hole.

Originally I had planned on full inverted oil and fuel, but that was before I had any acro experience. I now know that I can do most of the fun stuff without negative g and I don't really like sustained inverted flight anyhow. I do have a floptube in the left tank just in case I ever change my mind.

My panel is pretty much the basics but I did spring for a GRT engine monitor. Having a computer simultaneously keep track of all engine parameters gives me a warm fuzzy feeling. I have no vacuum system or gyros, but I stuck a Trutrak ADI front and center to help me live if I ever screw up and get into IMC. My compass is of the whiskey variety and I just added a Lowrance 2000c gps that does all the cool stuff at a very reasonable cost.

Engine will probably be Superior 360 carbed with a Catto prop. I know that a constant speed is cool, but I also know that this plane is gonna be a giant kick in the butt with just about any engine/prop.

I'll paint it myself and skip the $10,000 paint job. I also built the seats myself and they came out pretty darned good (considering a guy did the sewing).

I started this project back in 99 before all this glass panel, quick build, pre-punched, leather seat stuff got going. I look more to the budget builders for inspiration rather than the guys with the bottomless pockets. This is ceratainly not meant as a dig towards those building the fancy stuff, it's just not my scene.

Years ago I built a guitar and the coolest part was getting to shape the back of the neck to suit MY hand instead of having to adapt to somebody elses idea of the right shape. Build it to suit YOUR mission and ENJOY!!
 
I built my 7A for just under 80K using all new equipment, engine (0-360) and C/S prop. It is a steam gage panel with KMD 150, SL70 xpndr, SL40 com. For just positive G aerobatics, no special fuel or oil system is needed. These are 2004 prices, I painted it and did most of the interior, except seat upholstery. It is night VFR.

Hope this helps.

Roberta
 
Cameron,
The O-320 has plenty of power. My O-320 powered RV-6 has been doing all normal aerobatic maneuvers with no problems for over 13 years. I have a friend with a heavy -6 and a weak 150hp and he does full aerobatic routines regularly. You don't need the flop tubes unless you intend negative maneuvers, which the RVs aren't especially suited for anyway. The flop tubes also move your tank senders outboard 1 bay and decrease the usfullness of you fuel gauges.
There are many people who will try to tell you that you HAVE to have more power. It simply isn't true! More power is fine if that's what you want, but it is not necessary for an RV.
I know I will get flamed for this post, but that's my $.02 for what it's worth.
 
I agree 100% with what Mel said. Clearly, he's a smart guy!

Second, as others have said, your $50k budget is doable if you're careful.

You can find used tail and wing kits at a discount in Trade a Plane or if you keep your ears and eyes open around the homebuilt community. I paid $600 for my used RV-6 tail kit 11 years ago. That was a 40% discount compared to what a new tail kit would have cost. In addition, the $600 tail kit came with well over a thousand dollars of slightly used tools at no extra charge. I probably got the tail and tools at 25% of retail cost. I did something similar when it was time to buy a wing kit. In addition, I bought an engine core and rebuilt it myself.

If you're worried about whether you can handle a taildragger, get your tailwheel sign-off, or at least some instruction and make your choice at that time. With the slow build wing and tail kits, you've got a lot of work to do before you need to decide where the little wheel goes.
 
Jamie,
I'm not sure about the capacitance gauges. They may still work in the first bay with flop tube. My main point was that unless you intend pretty significant aerobatics, the flop tubes add extra cost and weight and don't offer any benifit without inverted oil and fuel injection, which again adds more cost and weight..
 
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Thanks for the info.

To give you all a better idea of what I want, I don't want to do any negative G maneuvers. But, even positive G aerobatics will get a plane in some fairly extreme attitudes and I just don't know if the regular fuel and oiling systems are set up for that or not. I just don't know enough to know what the limits of the regular system are. This is my hot rod background coming out, but all I can see in my head is oil getting away from the pickup during even the mildest aerobatics. I guess I need to see how the pickup is setup. Come to think of it, I don't even know if a Lycoming has a dry sump oiling system or not. Any insight or links to websites with good info you all could give me on this would be appreciated.

As for horsepower. I know what you mean about always wanting more power. I have a 69 Camaro in my garage with about 500hp. It used to be alot of fun, but then I started flying airplanes. My line of thinking right now is that even with the 160hp O-320, an RV7 will run circles around the Cessna 150 and the 172 that I have been flying. If and when the time comes, I will look for a 360 first, but I suspect that I will settle for a 320 if my budget won't allow the 360. I would prefer a mid to high time engine with a known history over a new one. In my experience, an engine that is about halfway through its life has proven that it was put together right, and with good components and it isn't likely to fail anytime soon. With a new engine, there is alot of unknowns and I want to eliminate as many unknowns as possible for that first flight. Plus, with a mid or high time engine, I want to do the overhaul when the time comes, but I don't want to do my first overhaul on an aircraft engine then put it in my first plane for its first test flight. Make sense, or am I just showing my ignorance?

I do plan on getting my tail wheel endorsement along with some tailwheel time after I get the endorsement. My concern is how much harder is a taildragger RV to handle than say a Cub or Citabria during takeoff and landing. I know that the RV7 is a sport plane and I also know that there are some planes out there that low time pilots have no business in. From what I have heard, the RV7 isn't one of these plane, but I wanted to get some more opinions before I decided what I am going to do.
 
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cgrossl said:
I do plan on getting my tail wheel endorsement along with some tailwheel time after I get the endorsement. My concern is how much harder is a taildragger RV to handle than say a Cub or Citabria during takeoff and landing. I know that the RV7 is a sport plane and I also know that there are some planes out there that low time pilots have no business in. From what I have heard, the RV7 isn't one of these plane, but I wanted to get some more opinions before I decided what I am going to do.
Click to expand...

I haven't flown the RV-7 specifically but I have flown the RV-6, and my RV-4 and have about 800 hours in my old Aeronca Champ and the RV-6 and -4 were both much easier to land in my opinion. They handle crosswinds much better and track fairly straight down the runway. The RV is fairly docile as taildraggers go but it will still bite you if you don't watch it. If you can handle a Citabria you won't have any problem with your RV.
 
Another budget item to consider while building: you stated you'd likely put 100-200 hours of flying in before your finished building. If your renting a spam can at, say $75/hr, you'd spend $7500-$15000 on flying during the build. For me, it's a compromise right now, getting ready to lay out large chunks of cash on items like avionics, instruments and an engine. Paying for the kits is pretty easy as you go. I haven't flown much recently due to putting more $$ into the plane for the large ticket items.
 
Cameron,

As far as aerobatics goes, the engine doesn't really care about the attitude of the aircraft, it is only affected by the loading. You can have a positive G load even while inverted. If you only want to do the usual sport aerobatics, you will never unport either the fuel or the oil unless you make a goof (which will only last a second or two - not enough to cause any problems other than to dump some oil on the belly of the airplane).

Serious negative G aerobatics does require inverted fuel and oil systems, but since that is not the mission you intend for your airplane, you really do not need to spend the weight or money.

Pat
 
Your idea of a mid-time engine is also a good one, especially if you plan to do your own overhaul. I started with a high time first run O-320 (2500 hrs), but with good numbers on oil consumption and compression. I flew the airplane for 300 hrs before OH, and even then, it was running great and all parts were within acceptable limits. The surprising part of this scenario is that you won't save a lot of money going this way. Overhauls are expensive, even when you do them yourself. You do save a little money and gain a ton of experience.
 
Pat,
I understand what you mean by keeping the plane positively loaded, but I'm just wondering how steeply you can climb, or dive and still not uncover the oil or fuel pickup. If you are climbing very steeply, there is only 1G on the aircraft, but all of the oil would be at the back of the sump. The same would be true during a steep dive, only the oil would be at the front of the sump. In either of these situations, I would think that after you exceed some climb angle or dive angle, the oil and/or fuel pickups will be uncovered. I would think that bank angle would have the same affect, as long as you aren't turning while you are banking, like during a roll. Isn't there some point during a roll where there are some negative G? Is it just not enough time to affect anything? My line of thinking is coming from my automotive background because I know almost nothing about the internals of a Lycoming engine. I guess I'm trying to figure out more about how these things work.

Mel,
I thought my line of thought was sound on the engine. I was hoping to save money by doing the overhaul myself, but if I don't save money, I still want to do it. I've built many car engines including several air cooled VW engines, which look very similar to a Lycoming. Overhauling an aircraft engine would be a great learning experience. I think that's the biggest reason that I want to build a plane. I'm bored to death if I don't have something interesting that I am learning about.

By the way, are there any other things that I need to consider before I decide to build?
 
I think you are thinking of "slow rolls" where you would have 1 negative g at some point. The typical rolls done in RVs are "aileron rolls". An aileron is so named because you only use aileron control as opposed to rudder input. This is similar to a barrel roll where you will keep 1 positive g throughout the maneuver. This is an over simplification, but the idea is that you can do them without inverted systems.
 
Mel,
When doing an aileron roll, or barrel roll, what is the center of rotation? I am guessing that since the plane is experiencing positive G-forces through the entire maneuver that the centerline of rotation is slightly above the fuselage? If the roll rate is high enough, I am guessing that centrifugal force during the roll is what keeps the plane under positive G loads throughout the manuever? Please correct me if I'm wrong.

Obviously, aerobatics are a long way down the road for me. It is starting to sound like I have a whole lot to learn.
 
A barrel roll is pretty much what a "corkscrew" type roller coaster does. An aileron roll is more or less the same deal, only less coordinated.
 
cgrossl said:
Mel,
When doing an aileron roll, or barrel roll, what is the center of rotation? I am guessing that since the plane is experiencing positive G-forces through the entire maneuver that the centerline of rotation is slightly above the fuselage? If the roll rate is high enough, I am guessing that centrifugal force during the roll is what keeps the plane under positive G loads throughout the manuever? Please correct me if I'm wrong.
Click to expand...


You've got it right, except that the axis of the roll is more than "slightly" above the fuselage. A typical aileron roll consumes 50 or 100 feet of altitude (You pitch up initially, resulting in a climb, and lose altitude while inverted). The slower roll, the more altitude you need.

There are a couple of rolls here from two different angles. Looking over the tail makes it a little more obvious, I think.

James Freeman
 
Great Video

James,

Great video! I'll definitely be reviewing anytime I need a little extra motivation to work on my plane.

Cameron,
I went through much of the same questioning before buying my 7 tail kit last week. Just to be sure I wanted a 7 i/o 9, I dropped the big bucks for an aerobatics lesson in a T6 Texan about 3 weeks after passing my checkride. Not only was it incredibly fun -- no doubt on the 7, but I learned a ton beyond just doing loops and rolls -- which were easier than I thought. We did unusual attitude recovery(similar to under the hood -- eyes closed, get disoriented, open eyes, my airplane...) but instead of mild stuff like during training, I was recovering from well past 90 degrees. Because of the positive G load, you have no idea how far over you are until you open your eyes. We also did a full stall -- which in a Texan means a MAJOR snap to an inverted dive (stick slammed so hard and fast it bruised my thigh). Obviously in the hands of a great instructor, not a big deal, but it definitely got my attention and gave me a much better understanding of some of the comments I've read on this and other boards about stall/spin accidents.

Long story, but the moral is I learned enough to know that I don't need an inverted system, but I definitely will be taking more aerobatics lessons in "3-5 years" when my 7 is done!

bill
RV7 (A?) -- working on HS rear spar!
 
I have a real horror story buying a used engine, never again. It could have killed me had I tried to fly with it. Some people, even fellow aviators, will lie to sell a used engine. Buyer beware.

Neil
 
plan and budget (long)

There are two places you start...planning your mission and examining your budget.

Other posters have correctly pointed out the need to articulate your desired mission, or the type of flying you think you will do. That is exactly where you should start (it's hard to believe, but if you go through this honestly, you might find you don't even want an RV!!). Alongside the main focus of what you mostly intend to do, flesh in some details of what you realistically MIGHT like to do...ie, cross country, aerobatics, night capable, haul four people, etc.

The next item (and the one where you'll really have to be honest) is to budget your funds. Be realistic about what you will be able to put into the airplane from a dollar standpoint. Go through this exercise several times, look at RV's and talk to people about see how they are equipped. Ride in an unpainted RV with no sound insulation and no instruments and foam pads for seats...light, yes...inexpensive? yes...but is that what YOU want for YOUR airplane?

Lots of people I talk to say that constant speed props are too heavy, all electric airplanes are bad, electronic ignitions are unproven, fuel injection is bad, etc. It just depends on what you the builder want... Do you buy new cars or do you buy 200 dollar specials and fix em up??

Here is where I differ from many in the "older" EAA movement...(soapbox please...). I think it is admirable that many people are so proud of aircraft they have built without spending any money, and I think that's great that they get to fly without much investment in money. Are you a born tinkerer? It might suit you very well to buy a used engine and rebuild it, or buy a used fuel injection system and rebuild it. Personally, considering it's an AIRCRAFT, I don't trust my skills at this point to do these things. I think more than any other hobby I've pursued (and I have too many!!!), aviation presents the greatest risks. I have been around homebuilt aircraft my entire life, and will tell you that most of the homebuilts I've known of that had engine problems (which have resulted in a lot of broken hearts) were of the homebrew variety. You need to rationalize your choices and justify every one of them before you move ahead with your dream airplane. My point here, and I'll probably get flamed...is that some people who don't posess the skills to "do everything themselves" and don't have the funds or time to put into their project should maybe find a different hobby. That's my personal view, based on what I see going on in the experimental world. I think it's unrealistic to expect that you would even WANT to build a 200 mile an hour aircraft to put yourself and your loved ones in for less investment than say, a nice new car.

I have built and raced bikes for dirt flat tracking and motocross, I've built and raced sand rails and off road dune buggies...but when it comes to putting engines in my airplanes, I made the decision early on that the engine and components would be new and or rebuilt by an aircraft engine professional. I admire guys who posess all of the engine experience and high technical saavy...but I will admit here, I do not.

I researched and reached my own comfort level with what I have installed in my 7A, but I think its important that you make all of your decisions based on hard facts and not rumor or gang thinking. It is amazing to me how many people think that because they are the loudest and most obnoxious, they are correct.

Now, for the last part...if I had to re-do my plane I would only change one thing, (besides taking more time to make the wiring neater) and that is I would put in a dual engine monitor efis and be done with the panel. I think at the end of the day, considering the install time and "cleanliness" of the panel, you get for what you pay for, etc...it's a no brainer. An electric attitude instrument starts at 1000 bucks and goes up from there...so $3500 on the full setup seems pretty reasonable to me...

Last tip, try to have personal conversations with the builders on this forum...some of the things you're going through right now are not best finalized by groupthink.

Good luck and enjoy the adventure...
 
RV-7(A)

I suggest learning to fly in a taildragger before you commit to a -7 vs -7A. I am also a strong proponent of 180 HP minimum in that type aircraft. Part of that is being based at high altitude and my suggestion to people asking about buying a plane to avoid anything less than 180 HP (resale issues).

I had around 200 hours when I first flew a -6A and learned to land and take-off competently quickly enough.
 
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