• ZN Line Evolis XL
  
  
• DPM Extra 330L
  
  
• ZN Line Evolis
  
  
• DPM Ultimate ARF
  
  
• ZN Line Madness
  
  
• MK Extra 300LS
  
  
• Kyosho Majestic 1400 ARF
  
  
• Kyosho G-Trick 90
  
  
• Thunder Tiger G-200
  

Introduction
Having flown the Dave Patrick designed Carl Goldberg Ultimate Biplane since 1991, I was very interested to see if there were significant improvements he could add to the this new Ultimate.

Certainly the concept of the kitting the Ultimate has changed. His new company Dave Patrick Models(DPM) is marketing this model in ARF form, and at 60.5-inch wingspan, 1230 sq. inches wing area and 64-inch length, is significantly larger in size compared to the previous design.

The kit, which comes in a huge box, is virtually complete, with almost all necessary accessories provided, along with pre-painted and installed canopy and cowl, pre-painted landing gear and wheel pants. All other surfaces are covered with Ultracoat (Oracover), and all hinge slots are pre cut. The build quality of the kit is as good as any I have seen in recent years, and most of the accessories in the kit are also of exceptional quality.

Design refinements are many; I particularly liked the 4 separate aileron servos, standard CF aileron horns, standard cable elevator set-up, pre-installed internal antenna tube, accurate cabane fixing and secure wheel pant attachment. Other details also impress, such as the easy yet secure mounting system for the aileron servos, pre-drilled holes for the cabane studs, braced tail, strong lower wing mounting blocks and vibration proof cowl mounting.

Also worthy of mention is the excellent instruction book, which details all construction steps with text and photos, as well as much food for thought in the flying process!

Construction
The kit came together easily. Although my work interrupted much of the construction of this kit, I estimate that the enthusiastic builder can prepare this kit ready for flight in 3 days. I did encounter several minor problems though, such as the tail brace screws were a little on the short side and some of the 4-40 bolts and nuts had defective threads. I also made a minor modification to the fixing method of the main landing gear, utilizing blind nuts instead of nylon lock nuts, and replaced the standard tail wheel with a Klett assembly.

Setup
I used the Futaba 9 ZAP WC radio with four 9602 metal-geared mini servos in the wings, 9204 on the rudder, 9601 on throttle and 9450 Digital on the elevator. My Ultimate is also equipped with the new large Futaba Rx switch and Duralite 1600 mah batteries. (Futaba Radios available @ Singapore Hobby Supplies)

I decided to power my particular Ultimate with a trusty SuperTigre G 2300. The cowl easily accepts this side-mounted engine, but I decided to make a cutout on the cowl for the slightly recessed cylinder head to ensure adequate cooling in Singapore's hot and humid climate. Necessary cutouts were also made for the exhaust, and for the engine's rather bulky carburetor.

The kit provides a pair of beefy looking engine mounts, undoubtedly strong enough to withstand the torque impulses of the large four-strokes, but I transferred my old Gator Soft and Safe mount to the Ultimate after its long and faithful service on a Goldberg Suhkoi. It mounted easily on the Ultimate. To complete matters on this end, I added a 545 c.c. MK fuel tank, mounted on the recommended CG of the model. Total weight dry came up to 5.3 kgs.

Flight Performance
How does it fly? Well, quite brilliantly. As advertised, this model, even at its current slightly nose heavy balance torque rolls very well. Rudder authority is powerful, and there is no pitch coupling on rudder, and only a slight roll coupling, mixed out easily on the radio and exactly in accordance with the instruction book. Rolling circles are effortless. Flat spins are flat, snaps are predictable, rolls are on a line and verticals are dead straight, just as claimed. It grooves like a F3A machine yet feels light and is a pussycat at slow speeds. Low wing loading pays dividends here! I might even consider modifying my smaller Goldberg Ultimate to emulate such performance!

A purchasing error resulted in the SuperTigre turning a rather large APC 18x10 prop(APC available @ Shivlal & Sons). Quite a surprising discovery as it suits the combination to a T and provides unlimited vertical performance, on 25% Cool Power fuel, yet sweet running characteristics. The large diameter also slows the Ultimate quickly for landings and spin entries.My first flight was a near disaster as I missed a grounding strap on the ignition that wasn't crimped and the metal-to-metal caused intermittent radio interference that almost put the plane in. I managed to get it on the ground without damage and found the problem. The second attempt was much more successful.

Overall
I am very pleased with the package, and am pondering another example, perhaps with a lighter engine, to come under the 5 kg requirement in the F3A rules…… - Chan Tze Law.(Tze Law is a F3A judge, and was judging at the Ireland 2001 F3A WC and Pensacola 1999 F3A WC)

• Relevant Link : Dave Patrick Models(An excellent looking Extra 300L ARF will complement the Ultimate soon. More information available at the DPM Web page).