Involving with Hobby

Long waited strawberry blossoms have begun to bloom at last and several harvest would be expected in a month. The season has changed into Spring now, that is suitable for Radio Controlled Airplane flight also, so I'm now in desperate efforts these days.

New FUTABA radio arrived at my hand yesterday with some disappointment for the appearance, especially face decoration with shinny chrome plating spoils it's value. But, great sophistication in it's actual functions is observed without partial eye. Probably, the work must have been carried out by the developing and experiment division of the manufacture company contributions with the top flyers desperate efforts. Fine attentions are discerned here and there in this equipment, FUTABA 10J T-FHSS AIR 10ch. The marvelous device like this gives me enough courage to exert myself in participating the future competitions.
Both of trainer airplanes, Rookie10 and Rookie20 was modified to have two aileron servos for aileron differential and flaperon actions. It goes without writing that new 10 channel Radio could make it possible to establish the full-fledged functions for F3A maneuver models.

Inviting YS fuel pressure injection system onto a small OS 25LA motor is now in good success after being hit several brick walls. First of all, any drum constructive carburetor need some modification to open freely the lower throat if it is used as part of YS system, otherwise the transition from slow speed to medium rotation would not be favorable. In addition, the smaller the combustion chamber volume, the more precise positioning of the regulator valve pressure adjustment is required, the tolerance of it not so broad as YS 60 motor at all, so concentrated and keen concentrated sense are indispensable when actual adjust is performed on the airplane engine mount. The purpose of this adjustment is obtaining the critical transient characteristics that is sharp and smooth from high to low and low to high.
Pressurized fuel supply made it possible to move the fuel tank backward onto the nearest CG position of Rookie 10, in addition,  also the far smaller size of Rx Futaba S-FHSS receiver could contribute to establishing a ideal weight layout in a small size airplane.

Just an application of a brass washer onto the needle valve here would be very helpful to eliminate some inconvenient hysteresis phenomena that inhibits very delicate needle valve adjustment. The silicon tube for preventing air inlet leakage set on the valve base portion often causes anti-movement action because of it's viscoelasticity and sticking phenomena.

Even a small part of peeling up of covering film on the left stabilizer lower inner portion caused an incredible result, making strange loud noise and inviting considerable aileron trim adjustment to  left. Also, this was the reason to have stopped test flight the other day.
One more turn main wing tightening rubber band should be added for two Rookies if any snap-role action would be tried, now a bit weak.
Though I have been in the Hobby of Radio-Control Model Airplane field as long as more than a half century since I was an elementary school child, still now I study much on every flight.

Believe in Web site?

Child's disaster happened the day before yesterday, the criminal might be a baby sitter employed through some Internet site. This problem was caused by a young mother with unwise thoughts. Very convenient the way as it is, are there any to construct a clear relationship of trust each other in the condition of the first meeting we can not see the face of other party. For example, any person can exhibit any thing, sometimes a white lie, in the Homepage, who can believe in the description content on Earth? There are no relief in the web site like Scientific field?
This is why I refuse firmly showing my own Homepage in the Web site so relentlessly these days.  

New Radio

30 years period of time absence from Radio Control Hobby field prevented me from flying two Rookies, both 20 and 10 yesterday. The reasons are shame to describe here, just ill connection of fuel tubes and pressure ones, also on 10 of reverse connection of one war valve. On the other hand, I could have the longing permission to take part in the Group in Mie prefecture. The way to use the flying place as a visitor paying some amount of money every time, week day flight is inhibited, this is why I made up my mind to be a member of the group.
I ordered new Radios, FUTABA 18 MZ and 10J, the decision should be done before the coming tax rate change. New models has indispensable capability not to be affected by another same frequency noise. Remembering the past, all of my lost model airplanes were done not by my mistake but by some external Radio disturbances. I can fly my planes without any outer disturbances is a dreamy Gospel for me.

Combustion motors

Chilly as this early morning was, AD motor in air-cooled VW Super Beetle declared some lack of fuel volume in Solex 34PICT3 carburetor, but intentionally leave I it's symptom of lean mixture untouched nand unadjusted. 3 days cold weather after 4 days warmer ones, we call it in this season, "3 kan 4 on" and the repeating would last till 20th March every year, also we do, "Atsusa Samusa Mo Higan Made."
Now, I admire again the capability of a computerized recent automobiles, because they can fairly control and automatically adjust all the environmental changes. Fully mechanical and conventional carburetor system suggests the fact.

I'm going to play with OS 46 LA motor that has no clank shaft supporting bearings in stead plane metal brass ones. As a matter of fact, we could be released from the threatening of bearing rust. Actually, I do not recommend the necessity of ball bearing supporting construction below 13,000 rpm operation of ordinary uses. Thanks to omitting heavy bearing, we can obtain much lighter power source with some similar power. De-tuned motor, LA series has a tendency to have smaller venturi in spite of bigger passenger port diameter(8,50mm for 46 crank shaft), so, the carburetor throat diameter could be enlarged to the same value. On the other hand, 2C carburetor for 21 car model has 7mm throat that is the same value of 60 FSR first generation, so determined I to set this smaller designed for 21 carb. onto 46LA.
Omitted schnurle scavenging main port would be engraved also gas way for that would be done inside the case that is a similar task with 25LA.

Radio controlled model airplanes

Rookie 20 trainer model airplane was operated on the stabilizer and the rudder in pieces to align them with precision, also, it's body was cut vertically at centric line like a fish cooking manner to correct distortion from the beginning of  fabrication. Because, old type YS regulator was found in my junk box, applied I it there without hesitation. Crowded fuel tubes and pressure ones are the same scenery as Rookie 10 I tried before. Replacement of the power sources from OS 25 FSR to OS 32F would change the character of Rookie 20 that is dull trainer plane into nimble acrobatic one with the special YS fuel pressure system! I was surprised to check the position of CG, that was to the point of that drawn on the design paper, how come? I replaced the motors from a lighter 25 FSR to a heavier 32F motor?? The result obtained revealed that Rookie 20 has been flown in the condition of tail heavy pitching balance from the beginning burdening a lighter 25 FSR motor.
Remembering the past flying scenery, it was relatively difficult to make landing smooth, too much tendency to stall every time. I'm looking forward to try this newly improved Rookie 20 on coming Sunday.
As the next step, Sukhoi Su31-40 ARF by Mr. Naruke is waiting for me to be set it's internal moving mechanisms, servos, linkages including elevator differential action for left side more down direction that dependent on actual out side loop attitude. Anyway, it is always some difficult and requiring patience and concentration with time consuming work. The twisted and distorted main wings have been corrected fairly previously, so it is waiting for my own determination just to start. Thick engine nacelle might invite any vibration resonance, so reinforcement inside of firewall would be indispensable at all.

YS fuel pressure regulator

No matter how it may be, a conventionalｌy mechanical controlled or fuel injection, any aberrant of dust into fuel line should be avoided, otherwise the throttle valve would not work fairly with smooth operation as designed. YS injection system utilizing crank case primary pressure in 2 cycle motor hates and easily loose it's performance, some crazy action at higher speed and unstable main needle valve angular position are the symptoms of dust invasion in the fuel line, most of the time, any fiber dusty material should be sticking at the valve portion. It was sure enough that a visible piece of fiber dust was found in YS regulator!
Remembering the bench test yesterday, high needle position was not stable repeating hi after low rotation. Fuel measuring was not performed adequately because of this damnable enemy, fiber dust! Motor stop situation sometimes brings the accidental airplane destruction.
An oldest YS regulator in my junk box was disassembled for careful inspection, the heart valve diaphragm inside has  different construction with metallic part at centric position. It's a matter for regｒet that the diameter of the silicon rubber is 2mm smaller than that of newer models, the size of them were redesigned. The precise guiding rod height and fitting of moving valve with the valve holding case are the most important requirement for this kind of diaphragm valve construction.
2,6-0,45 drilling tap set and 2,1 mm drill tip were prepared for a further processing to combine YS regulator body and the coupler part made by Lost-Wax method. Once tried, but failed because of casting error, lack of the casting metal material bulk. Special muffler adapters would be manufactured by my own hand making at the same time. K&B Torpedo 45 R/C and OS muffler, Forster 32 and OS old band fixing type muffler promptly for the future entry to Golden Age competition.