O-320 engine mount

[vern]

I'm planning on a Lycoming O-320 on my Hatz. Has anyone with an O-320 had any CG issues?
Mind sharing how far from your firewall to the engine mounts?
Tips? Suggestions?

Thanks!

Vern Darley
Hangar D30
Peachtree City, GA
vern@mindpring.com

[dougm]

Do you have a complete set of plans? The Classic plans include all the drawings and measurements for an O-320 engine mount.

[Ebby]

Respectfully, I have HATZ Classic plans #37 and there is no engine mount plan sheet. Did Makelan add a page? I do have CB-1 plans and there is a crossed out sketch of a O-320 engine mount.

[dougm]

Take an inventory of the pages you have and contact Makelan for the ones that are missing. I did that a few years ago. A complete set of plans should include drawings for things such as: Engine mounts for O-320 & Rotec R3600, Landing gear for O-320 & R3600 (longer gear for the radial due to longer prop), cowling, throttles, headrest, windshields, and others. Don't remember all of them, but I was missing several pages when I first received drawings for s/n 093 and Jeff sent me what I needed after I told him what I had.

[jptowey2]

Hi all --

I recently purchased and received a set of Classic Hatz plans (#187).

There were a total of 30 sheets, numbered 00 thru 27.. with 00R, 17R, 23R being specific for the Radial Engine Option.

Doug - I noticed on the Radial Engine Mount sheet it called out the moutn for Rotec 3200 vs. 3600. Is this consistent with your plans? I'm a LONG way from worrying about that -- but figured I'd confirm while the topic was hot.

Thanks --

[dougm]

Jim, that's a typo. My plans say the same thing.

Rotec makes two radials:
R2800 (2800cc, 110hp)
R3600 (3600cc, 150 hp)

There is no R3200, the plans should read R3600. The R3600 is the same 150hp as the O-320 and virtually the same weight so there are no penalties regarding weight, cg, or hp.

There are many typos in the plans. You'd think that something like blueprints would be error free, but nope. Study the drawings, read the dimensions, and cross check one drawing against another to ensure you have a clear understanding of the part you are looking at. Some are fine, but others need some double checking.

[jptowey2]

Thanks Doug --

I was figuring it was a typo, but appreciate the confirmation.

I know there is a whole category called "Plan Discrepancies", but I was wondering if anyone had a compiled list (in word or excel) of all the known issues to date?

If not, since most of my near term time is going to be going over the plans and various builder pages -- I will attempt to get a single list generated and share with the group at some point before the end of the year.

[Ebby]

I'll look into getting he missing pages.

Thanks as always.

[HC85]

Hello, I see that your question was not answered.

The GG of the Lycoming engine is 19.175 inches from the centerline of the upper most forward fuselage cross member tube.

For the Rotec 3600 it is 14.175 from the lower most forward fuselage cross member tube.

An interesting note is that I found the CB-1 fuselage to be 2.75 inches longer than the Classic's. I think this is because the cockpit on the Classic was laid back , moved back and as a result the aft section behind the pilot on the Classic was shortened to compensate for the added moment of the aft pilot being moved back.
Also, I think the tubing size on the Classic is bigger than the CB-1 aft of the rear cockpit, to compensate for the reported "tail movement" reports for the CB-1 in flight? ( Also the perhaps the reason for duel flying wires on some CB-1's and not the Classic)

I have read that there is not much room aft of the engine (s) and it makes maintenance and installation more difficult. I was considering making the fuselage the same length as the CB-1 and taking my engine out further, because I think the tail moment is already short on the CB-1, why make it any shorter?

[Ebby]

Emailed Makelen regarding the extra pages for the Hatz Classic and received no reply. I used Jeff@makelen.com. Is there an updated email address?

Ebby