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Pre-construction planning questions

sbalmos

sbalmos

Well Known Member
Sponsor
Hi all,

New here (or at least I was as of this past weekend), in the midst of doing lots of planning, cost rationalizing, etc of the 9a. I got to meet with Andy (Lionclaw here) and see his just-finished 9a.

Anyway, a few questions...

1) This may be answered in the Preview Plans, which are on order... But can anyone give the dimensions of the subkits, such as each wing by itself, the fuselage from firewall back to empennage mount points, etc? I'm trying to measure out how much I can build separately in my 15' long condo garage.

2) I've noticed in here that a few people have mounted IO-360s (especially Mattituck's) on a 9/9a. I thought that going above a 320 was highly recommended against because of the ease of going over Vne?

3) Andy mentioned how he had to do some cowling mods to fit his O-320-B. Can anyone give a general list of which submodels of an O-320, or I guess an O-360 also, are "easier" to mount in the stock cowling?

Just the start of most likely many planning questions. But everyone's used to that, right? :)

Thanks!

--Scott
 
I can?t give you the dimensions of the parts but your project will take up as much room as you have available for it.

As for the IO-360, I?m assuming you are talking about the 180 hp parallel valve version, not the much heavier 200 hp angle valve engine.

There is no real need for the extra HP in the -9/9A. I started out with a 135 hp O-290-D2 and was very happy with it. After I trashed that engine, I installed an ECi O-360 kit that I put together with the help of an IA friend. Truth is, it is not needed as I typically throttle back and fly around at 150 knots anyway.

Remember, the -9?s GW is limited to 1750 lbs and the -7?s is 1800. This it is imperative you keep your empty weight down and the smaller engine will help you do that without giving up more than a few points in performance. Besides, a lighter plane flies nicer.
 
As mentioned, the weight difference is 15 or 20 lbs between the two engines. I've resolved to go with the (I)O-360 and low compression pistons so that I can use a lower octane fuel (should 100LL go away) or autofuel. My research indicates it will produce about 170hp. My plan is to throttle back for fuel savings (45-55% and LOP) but climb rate will likely be slightly improved at WOT. I doubt 10 additional horsepower will launch me irretrievably outside the envelope.

That's my thinking anyway. :rolleyes:
 
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Scott,
What I learned yesterday was if you have friends with 4s,6s and 7s and you go to fly with them you are running full throttle most of the time on O-320 with FP just to stay in the group :D IO360 and CS would be nice in this case.

If you fly high and far alone you would be happy with 320.
 
"there is no replacement for displacement"

One can always throttle back and get the same fuel economy with a 360 as with the 320. Weight difference is maybe 15 pounds, so in my opinion, that's not much of a price to pay for the extra horsepower. I run 8.5:1 pistons and premium mogas. I like having the bit of extra kick, especially flying at higher altitude. If going with certain engine-prop combinations, there are some rpm restrictions with the 320, but I am not aware of any with the 360.

Nothing wrong with the 320 (or even the 235) but I like my 360 just fine. No issues with cowl adjustments in my case.

My two cents worth.

greg
 
O-320...

I'm building an RV-9A and Van has an interesting paper on the O-320 as the max engine:

http://www.vansaircraft.com/pdf/hp_limts.pdf

Making changes because you feel authorized is a dangerous direction. Bigger engine? I'm sure it is withing the safety limits! Add 100 lbs. to the gross weight? no problem! What is the Real VNE? I'm SURE it is OK to add a few knots!

I did not design the plane, I'm just assembling it, so I gotta go by the rules the designer setup.

Unless I'm the designer, taking into account ALL the variables, I gotta do what Van says.

Dkb
 
POH or real world limits?

I set the limits in the POH to that what Lycomings sets as the maximum. Now in the real world if you chose to operate at lower limits that is fine. My POH says what Lycoming says but my Dynon is set to alarm at my personal chosen limits. Why this drill? If all goes sour and you have to have a chat with the Frendly Aviation Administration or your insurance carrier you will be held to the limits in your POH. Even thought I choose real world limts lower I don't want to potentially shoot myself in the foot in case I am called to task by the "Higher Authority" and remember that many of those guys see no shades of gray just black and white.

Pete
 
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Empennage...no problem in your garage.
Wings....require 133" to hang in the stands. Plan on at least a foot on either end to accommodate posts and workspace. It should fit (tight but it will work)
Fuselage...not sure on dimensions but it is 20' 1/4" from tip to rudder. The rudder is easily 12-15". You need to subtract off the length of the cowling. You may be able to build it in your garage without any of the firewall forward stuff. Check with Vans to be sure.
One thing to ask yourself...where are you going to store finished parts?
Welcome aboard the VAF and best of luck to you.
 
Some measurements from what is taking up space in my 3 car garage (still have room for the wife's car!).

Fuselage is about 14.5' long from rear bulkhead to firewall. Cowling and spinner will add over 4' to that length. Adding the tail/rudder will also add to that length.

Wings with tips on are about 13.5' long.
 
Thanks for the info everyone! Sorry I haven't responded. Was away on a business trip.

I'll most likely stick with the -320 for now, unless I come across a sweet -360 deal. Mainly building this for myself to go wherever. But it's always helpful to have a little more under the hood. I'm just down to the incessant carb or FI debate. Carb = lower fuel pressure running through the line, have to deal with carb heat but oh well. FI = no carb heat, supposedly smoother individual fuel flows to each cylinder (how much does this *really* affect things?), but the idea of an order of magnitude higher fuel pressure in the feed line kind of irks me (even though all I've ever flown was a FI'd 172. :D)

I'm clearing out the (useless) second bedroom in my condo to see what kind of work area I have there, in addition to the garage. At worst, there are a few heated storage unit places around here that I can store the completed sub-assemblies in, and possibly set up as an additional work area. There are always ways around everything.

In other news, last weekend I passed my PPL checkride with the (in)famous Martha Lunken (a very sweet old bird, by any accounts). Ended up being more of a joyride than checkride. So at least now I can actually fly any of these planes I'm dreaming about building. :D

Thanks again all! Obviously more questions to come as I read the massive binder with the preview plans that's sitting on my doorstep this morning.
 
Congratulations on passing your joy-ride. Reading the manual is a good thing to do but in my experience, it makes a whole lot more sense when you have the parts in hand. My advice is bite the bullet, order the empennage and a tool kit, and build a bench while you're waiting for everything to arrive. It probably wouldn't hurt to buy the practice kit too.

In any event, persistence is what completes these kits and the sooner you start, the sooner you'll finish. You'll be really surprised at how quickly the empennage kit goes together and how encouraging it is over-all.
 
Don said:
Congratulations on passing your joy-ride. Reading the manual is a good thing to do but in my experience, it makes a whole lot more sense when you have the parts in hand. My advice is bite the bullet, order the empennage and a tool kit, and build a bench while you're waiting for everything to arrive. It probably wouldn't hurt to buy the practice kit too.

In any event, persistence is what completes these kits and the sooner you start, the sooner you'll finish. You'll be really surprised at how quickly the empennage kit goes together and how encouraging it is over-all.
Click to expand...

Ditto on this. Don't waste time with little details and the minutia of how you are going to do this or that. As Nike says...just do it!!:D
If money and time are not an issue then bite the bullet and get started...YOU WILL BE GLAD YOU DID!
 
Heh. I wish I could say money is no issue Aaron. That's a large chunk of why I'm still waffling. I'm just a "lowly" software developer. :)

I'm going through lots of calculations right now of the total build / ownership cost - touring local hangars, figuring out their rates, trying to figure out the probable insurance rate, etc. I've got a dream configuration figured out. I'm just scaling back now, in spreadsheets, on that - the vast majority in the avionics, of course.

The big thing that's biting me right now are the hangar costs. I'm being quoted anywhere between $3k-$4k annually, which hurts. You've heard of house-poor. I don't want to end up plane-poor.

Oh well. Just more rationalizing to do...
 
sbalmos said:
Heh. I wish I could say money is no issue Aaron. That's a large chunk of why I'm still waffling. I'm just a "lowly" software developer. :)

I'm going through lots of calculations right now of the total build / ownership cost - touring local hangars, figuring out their rates, trying to figure out the probable insurance rate, etc. I've got a dream configuration figured out. I'm just scaling back now, in spreadsheets, on that - the vast majority in the avionics, of course.

The big thing that's biting me right now are the hangar costs. I'm being quoted anywhere between $3k-$4k annually, which hurts. You've heard of house-poor. I don't want to end up plane-poor.

Oh well. Just more rationalizing to do...
Click to expand...

I totally understand. I don't want to be plane poor either. I have three little mouths to feed and send to college and that is more important than my plane. I have just accepted the fact that my plane is going to be simple with no real whiz bang gizmo's or fancy paint jobs but it will fly and it will be fun. I have also accepted that this project is going to take me longer than the average Joe because of those things.
Money is always an issue...do your best planning then add 15%...that should be pretty close to the final number. Is there someone who has space locally to you that would let you use/rent it for cheaper than hanger costs? If I were paying rent then I would attempt to build it as quickly as possible. Keep in mind, your income SHOULD go up as you progress through your career. Good luck to you!
 
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