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PostPosted: Tue Jan 10, 2006 7:12 pm
by uscgairdale
I do my best to search through the archives on this and other sites before asking any questions, but I have yet to come across any performance numbers on the two-place. Most likely due that there weren't that many.

I am curious to know the basics like cruise speed, best rate of climb, ect. I just got some KFMs, but specs for the JPXs is just fine. I am assuming(dangerous word) that I will have better climb numbers. Also any useful tips would be great. For example, I heard that the previous owner of my machine used to fly with some ballast in the other seat when solo. Is that really necessary? (FYI, I tip the scales at 150's all muscle though! ha ha!)

I am also in the process of throwing punches with our good old friends the FAA about the Lazair II's rightful place in the LSA category. The LSA rule specifically rules out twin engine aircraft, but I am going to try anyway. I am hoping that because I fly a multi-engine helo for the Coast Guard and hold a commercial instrument rating that I may be able to obtain some sort of variance. You know, wish in one hand and you know what in the other and see which one fill up faster sort of a thing.....


PostPosted: Wed Jan 11, 2006 1:56 am
by JPXman
you want performance numbers? i can only give you what i have seen in my 2-seater with a regular 0-80 ASI and an altimeter (no VSI) and JPX engines, 280 pound pilot:

take off: 25 indicated
climb: 25 indicated
cruise: 40 indicated
approach: 40 indicated, if not 45
flare: 40 indicated

this bird is big and lumbering, keep the speed up. i get around 200 fpm climb.
i took a buddy up who weighed 190 pounds and we did a whole circuit and never got above 200 feet....

but its a lot of fun out in the open with an extra seat :)


PostPosted: Wed Jan 11, 2006 2:17 am
by ozzie
dave, i went thru the same thing here in australia . no twins permitted !
i got in on the grandfather clause ie it was flying before your rules. may be that approach may work for you. they may make you do a proper twin endorsment to carry a passenger. a good responsible trade off. good luck ozzie

PostPosted: Wed Jan 11, 2006 9:26 am
by Shannon
Spec sheet

PostPosted: Wed Jan 11, 2006 8:17 pm
by Chappy
Way back when I was lucky enough to get the chance to fly the two place prototype. It was only fitted with two Rotax 185's with bi-blade props. It was a lot of fun to fly solo, not very different to fly than a single place. Two up was a whole other story! Climb was pitiful, and took a good bit of skill to extract. This was my wife's first flight in a Lazair (or any Ultralight) although she was working on her pilot's certificate and was well past solo by that time. She could not keep the Lazair at altitude, rather slowly losing altitude whenever she attempted most maneuvers. I would slowly (very slowly) climb it up to a couple thousand feet, then let her take the controls and slowly down we would come. I would guess we were somewhere around a 340 pounds load back then. BTW, there was no airspeed indicator on that plane, and it was fitted with an old, early series 1 light spar wing.

My first landing was rather hard, as I let the approach speed drop too low and I let the plane get into a rather surprising rate of sink. The position of the overhead stick contributed because it's not in the place you're used to in the single place. I thought I still had some back stick to use for flair, but the stick was just about all the way back. I got the engines spooled up just as we contacted the ground. I was very embarrassed as I did all this right in front of Dale Kramer, who had trusted me with his only prototype. I'm surprised I didn't wipe out a wheel or two, or worse. It's like flying with floats, you really need to keep your approach speed up.

I never owned a 2-place, but I flew them quite a few times at Sun 'n Fun, Oshkosk and the factory when I worked there. I thought the performance of the 2-place with KFMs (and also the ill fated Westlakes) was quite adequate, and sure got spoiled by the electric starters (KFM). I've never flown the JPX, so can't compare with them. If you flew in really awful winds, you might want ballast. Dale K. suckered me into doing that once for him (serving as the ballast) in ridiculous winds. It was the first time I REALLY wished for a parachute!


PS. Dave, I would also suggest pushing the FAA for Grandfathering of your 2 place Lazair. Call EAA and USUA for help! If you can get yours accepted, you can set a precedent for the other Lazair II owners here in the states. If unlicensed operators have successfully been flying 2-place Lazairs for twenty years, certainly the FAA should be able to accept licensed operators doing the same under LSA!

PostPosted: Thu Jan 12, 2006 2:35 am
by ozzie
be a good idea to assemble a complete 'data package' on the II.
maybe dale k can help here. also obtain a aircraft condition report to present with it. listening to roy's show on the net over the last year it seems that our systems are similar. i was spared the pain of the data package as one was done in 1986. so you will help others down the track. but i still had to do a history and condition inspection. cost 200 bucks. did dale ever proof test the structure or was it all slide rule.? ozzie

PostPosted: Fri Jan 13, 2006 5:42 pm
by uscgairdale
Man, thanks for all the good performance numbers. I'm not suprised that you guys came through again. I am definitely glad that I sprung for the KFMs. I thought that just a bit more power is a good thing in the case. I also like being able to start the left engine from the right seat with the electric start. I hope that I don't get to lazy though.

As for the FAA, I am not trying to get my hopes up, that way I will be pleasently suprised if it works out. Yea it's multi-engine, but it's still an ultralight trainer. Not to mention that you can probably count the number of them on one hand. Sometime next week I plan to contact the Boston FSDO as I have all the contacts there. I'll of course keep everyone posted......


PostPosted: Tue Jan 17, 2006 2:47 pm
by JPXman
like dale said, i should get a mack truck hood ornament for my 2-seater :)

and i guess Dave you'll have a Lazair II EL according to shannons data sheet! you'll have the only one of those around i think that's flying. Larry Fish has a 2-seater with KFMs however he seems to have fallen off the face of the earth?