Mr. Hirata's comments

Mr. Hirata gave me some comments, who assembled Gladiator II introduced by above pictures. This might be the first time for him to assemble such a type of linkage as used by the Gladiator II. He seemed to have much fun like solving a Puzzle. He tried to make Gladiator II based on the design by Mr. Cermak as far as he can. However he adopted conventional piano string linkage based on his many experiences. The original wire linkage uses steel string, so there is few weight increase, even if the piano string is used.

It looks like that Mr. Jaroslav Cermak uses F3J/F3B model technology, because Lubos Pazderka(manufacturer of Eraser) seems to be a good influence on him. It is not coincidental that the URL of the web site of Mr. Cermak(www.f3k.cz) is similar to that of Mr. Lubos Pazderka (www.f3j.cz). If Gladiator II is the model for slope, this approach is quite natural. My point is that Gladiator II is the DLG that must be light enough. The main plane is molded using the 3 layered structure with glass/balsa/glass sandwich that is familiar in the F3J/F3B model. Using shell-structure, The inside of the main plane is empty but stiffer and light, compared with the main plane made of the foam with Balsa plank in the past, even if the surface is flexible. The surface of Gladiator II is not harder than Radina DLG that use similar technology. However the main plane as a whole is to be stiff by a spar and strategically placed carbon reinforcement on it.
By comparison of the plans of Gladiator I and II, you know that Gladiator II has double dihedral at the center and quarter of the main plane, Gladiator II has a single dihedral. If you hold the main plane with section HN profile, the Gladiator II (HN487) is obviously thinner than Gladiator I (MH32). The high performance of airfoil of HN has been already proven by the NYXs and New Sting and so on. A thin airfoil is, theoretically speaking, good for the fliers from the view point of penetration and thermal duration, it is not good for the manufacturer to make a thin main plane without torsions and to make a thin plane be stiff. Some high technologies must be required. Gladiator II has successfully realized it .

As for the aileron linkage, such a technology is adopted that is used by the FIREWORKS3 developed by PCM in Germany. The aileron servos should be installed in the fuselage in order to concentrate the mass and reduce the rotational momentum. Therefore it is the problem This technology is familiar in the area of the V-tail linkage for the open class airplane. It must be a challenge to use such linkage for DLG/HLG. It is clearly easy to establish a linkage with aileron outside fuselage. It is very elegant to accommodate the aileron linkage into the fuselage, but honestly speaking, it is not welcomed for old fliers that the reading glass and tweezers are required to conjunct aileron linkage and the aileron lever.

The fuselage of Gladiator was changed from with the canopy to nosecone. The vertical radio gear mount enables us be easier to accommodate receiver and servos in to the fuselage as shown in the above pictures. The nose length of Gladiator II became to be longer than that of Gladiator I. As for the center of Gravity, it is well-designed so that the gravity center locates as designed with almost no ballast just after installing the receiver, servo and buttery. The span of wing became 20mm longer and the length of fuselage became 38mm longer than Gladiator I respectively. On the contrary, It is excellent that the total weight was reduced about 20-30 grams. Because the fuselage (boom portion) diameter is large enough, Radina DLG is so strong enough that we can fly Radina DLG without feeling any anxiety. Gladitor I has very skinny fuselage, some fliers broke fuselage when it was launched with his full-power. It is chief reason that the strength of carbon pipe in the fuselage is not enough as well as the structure of pod of the fuselage. Here is a comparison about the diameter of the carbon fuselage pipe at their root.

The fuselage pipe of Gladiator II became strong enough to swing with full power. The fuselage length of Gladiator II is 117.5cm, the longest in those three models, which is about 4 cm longer than Gladiator I. The fuselage length of Gladiator II in the picture is 117.5cm, which is 6cm longer than its design so that the center of Gravity locates as specified by its design. But the nose ballast was only 5 grams.
The JETI Rex 5 Plus(FM PPM 5 channel) receiver is used. It is light and small enough. But it is sometimes interfered by the electro-magnetic environment. So the antenna was spanned outside fuselage. In usual, this is not required. (The transmitter is Futaba FF9 which can transmit signal 6th channel output signal through 5th channel. Therefore 6 channel is not required by the receiver.) As for the servo, GWS PICO STD (Torque:0.8kg, Speed:0.10 sec/10deg. Weight:6g) is used. Since GWS servo is not always reliable, but it is cheep, which is acceptable enough for DLG. Total weight is 330g. However I have an impression that Gladiator II become greatly lighter than Gladiator I.

The tail plane is simple balsa plank with Carbon roving reinforcement, but without Oracover light. It maybe enough, but Mr. Hirata cover the tail plane by thin film. (This is a matter of the individual)

Gladiator II reaches to higher altitude than Gladiator I. It is about 35-40m at least. The long fuselage makes its flight be stable. Mr. Kanoh, who is famous as a missionary of Radina DLG in Japan, recorded the flight of his Gladiator II by LOLO2, which shows 45m. If airborne condition is good, 50 m will be possible. The response to the thermal by Gladiator II is quite well so that we can find thermals easily. When Gladiator II meets the thermal, it does not respond too much to it, therefore we can control Gladiator II easily and enter into the thermal riding on the thermal.
The comprehensive flight impression that Gladiator II is one rank higher than Gladiator I and the conventional DLG such as Radina DLG. (Radina DLG became a standard in Japan.)

Here is the standard trim setting and the trim by Mr. Hirata.

The trim by Mr. Hirata is gentle, it can be wilder according to favorites of the individual.