This Unique Marcel Jurca Design Is A Must See For AirVenture 2022

By Anthony J. Liberatore

If you stop by EAA’s Homebuilt Hangar at the northern end of the AirVenture field, you never know what gem of a homebuilt will be on display. It was by chance that I stopped by the Hangar on the pre-event Sunday, and the ariel Hot Rod in the Hangar certainly got my attention. There it stood on its tall retractable taildragger gear with a modern low drag cowl and an empennage full of P-51 DNA. Painted in a light gloss Gray with a long sliding canopy for two in the tandem seating configuration. The wings were unique, No Dihedral, which is a design hallmark of the late Marcel Jurca.

I approached the builder and asked him about the lack of Dihedral and how it reminded me of Marcel Jurca’s all Wood Sirocco, and he noted, yes it was like the Sirocco he had built. My brain lit up, as many years ago in my EAA Chapter in Connecticut (Chapter 166) there was a Sirocco, which is a rare homebuilt. I immediately looked at the name tag on the prop and I was amazed, it was my fellow chapter member from back in the day! I reintroduced myself and noted we had met many years ago. The builder of that Sirocco and the MJ-51C “Sperocco” is Lowell Manary.

Lowell and I were actually co-workers as well at Pratt and Whitney, and it has been years since we have seen one another as career changes and moves can do that. However, it is amazing that the common place we often reconnect is Oshkosh.

Lowell proceeded to answer my questions about his amazing steed that looks like a cross between a WWII Warbird and 30’s Racer with its dashing good looks. It wasn’t until I researched NLM3 further did I find out that on its maiden trip to Oshkosh in 2021, NLM3 won the Grand Champion Plans built Gold Lindy award. Lowell explained the genesis of the design and his interaction with the late designer Macel Jurca.

Lowell said, “I originally went to France, showing Marcel, three quarter Spitfire that I was going to make, a two-place tandem and at the time, however Marcel was busy with designing a scale ME-109. I spoke with Ken Hide the Michigan salesperson for the plans, and he said that he (Marcel) had done the same a P-51 in 2/3 rd ’s Scale. The Ken said there was one being built out at a local airport, so we went out and looked at it. It was 200 hp (maximum hp) flat wing (no Dihedral). I thought well, it'd be easier to make so I bought the plans. And then we started negotiating with them, (Marcel Jurca) and made changes to handle the power and weight of the IO-540. We also rounded the bottom (rear fuselage), and it was designed to handle 350 hp.”

Those were not the only changes that make Lowell’s MJ-51C unique. Lowell also changed the original NACA airfoil section in the plans to a Ribblett 37 Series Airfoil with a constant chord thickness of 15% all the way out to the tip with a half a degree of twist. Lowell said: “Ribblet suggested that I put a half a degree twists in it, not for stall, but to make the air think it's on going over an elliptical airfoil for cruise, so it's got a half a degree twist in it for cruising.” The wingtips also incorporate the Late Harry Ribblet’s recommendations of keeping the trailing edge of the wingtip square to the fuselage which gives it a bit of a swept look on this tapered wing platform. The Flaps and Ailerons are also Lowell’s design and he noted how effective the flaps are at the 40° setting. The Ailerons almost defy description with all their design details. They are a Frise Aileron with a generous leading-edge radius not to induce a stall when they protrude below the wings lower surface, with inboard built-in spades/mass balances to boot. They might be considered slotted even though the aft trailing edge they mate up too shares the same generous radius. The Flight controls are all pushrods with heim joints, other that the rudder which is by cables on straight run pullies.

When I asked about the handling characteristics of the MJ-51C Lowell said: “Hold your finger up, when you fly cross country” and he pushed against my finger with the slightest of pressure, he then said, “It’s that, Now If you want to roll it.” Lowel applied just a bit more pressure, “It's like that.” Lowell said the stall speed with full flaps is 60mph and noted, “I can tell you is it has no tendency to drop a wing, you get an inboard buffet and it's nice and gentle, and you can fly it around with it buffeting and by comparison it makes the Cessna 150 a wild stall,” NLM3 will cruise 200 mph at 60% power with an economy cruise fuel burn rate of 10gph.

In terms of range Lowell said, “I can do 800 miles to from Colorado to relatives in Missouri, in four hours at economy cruise an and still have enough in the front tank to go another 350 miles.” NLM3 is Powered by a Parallel valved 540 out of an Aztec it is stock except the tuned cold air induction, and a Lycoming test engineer told Lowell it’s good for an extra 15 hp for a total of 275hp. with the current propeller limiting his maximum rpm to 2550 it’s putting out 265 hp. Lowell said: “If the propeller didn’t slow me down it would be 275hp.” In terms of top speed Lowell said: “at 19,000 feet the airplane at full throttle and 2300rpm it will cruise about to 235mph.”

NLM3 first flew on July 6 th , 2019, with long gestation period, however that timeframe was full of life events as Lowell explained: “I started long ago, but I finished a job at Pratt. I rebuilt a Corvette and sold it when we moved to Colorado, I worked for Western skyways building engines for a year and I built the house so for a year and a half we had nothing to do but store it and probably the add up all of the years condensed I probably got a good hard 17 years in building it”

FMI: www.eaa.org