Basic Aeronautics

[KENNYGLIDE]

Yeah all makes sense.Thanks...I heard on the grapevine there are some plans for a corflute SCANNER.. anyone else heard of it?

,

[Brian Clarey]

Weight!!
Weigh must be considered in conjunction with Wing Area ie By dividing flying weight in ozs by wing area in sq feet. The resultant is expressed in oz/sq foot --imperial measure or grms/ sq decimeter metric measure. Charts are available (Nomograms) for this. By reading off this table a suggested ballast loading for a given wind speed, is obtained. This ballast must be placed at the COG, so as not to upset the air crafts trim. Secondly , the structural integrity of the model must be considered in the event of harsh landings with added weight..

Brian C

[Celwin]

JR showed me.a diagram of what someone did (online) to prevent groundloops and general tendencies to be difficult to keep straight.

[KENNYGLIDE]

Marcel..do you know what the situation is with the plans for a corflute SCANNER?

[Brian Clarey]

Drag is produced by an object trying to penetrate wind speed. Typically FRONTAL AREA v`s WIND SPEED. The greater of either or collectively--- the greater is the power required for penetration to windward. It is therefore reason to assume that parasitic drag and induced drag can be attributed to any proturbances added- that effect the smooth passage of the air stream over the object. AIRCRAFT have the addition of undercarriage ,motor/muffler combo. dowel for mounting the wing, gaps at the control surface hinge points. Wing tips create turbulence . ie.---A spiral vertex from each wing tip and stab/rudder is produced..

Brian C

[Celwin]

I have a Waco biplane (competition for the Stearman at the time) which flies very nicely and scale like, but I was always afraid of a dead-stick because of parasitic drag. They apparently have the glide ratio similar to a brick.

I wonder how much difference taping the hinge gap on a Scanner would make. I doubt it would be visibly noticeable but on-board telemetry may show it.

During WW2 aircraft companies were discovering how important it was to reduce parasitic drag. Wing fillets became crucial and very obvious (such as the spitfire) and flush-mounted rivets became standard issue. The aircraft that bucked the trend was the Junkers JU52 Tri-motor. It had a skin of corrugated aluminium. Lots of surface area and associated drag there! (but still a very successful aircraft for many decades).

[Brian Clarey]

Power; Ie. Thrust and Torque . The more thrust , the greater the torque. This can have adverse effect on high powered aircraft during take off-- so much so that due to the torque fed into the air frame from the motor, a wing tip could hit the ground causing the aircraft to cartwheel down the airstrip.
Counter measures had to taken , by feeding in correction with rudder etc. Numerous high powered fighter aircraft during the second world war were lost due to this problem. The discussion here is to highlight the topic of side thrust and down thrust,as built into model aircraft. This problem was addressed with rubber powered Wakefield models by experimenting with down thrust and side thrust. ..We`ll consider down thrust first.--As indicated it means that the trust line is angled downwards. This angle, combined with the angle of attack of the wing, can create adverse handling, if taken to excess. Similarly with side thrust- too much will create excessive yaw. This indicates that each model must be trimmed individually with initial test flights are performed.

Brian C

[Brian Clarey]

Since the government has confined us all to barracks for several weeks, I have a thought, that a new project may be appealing to some members. What I have in mind is an aircraft that is the culmination of your own thoughts. Through a series of threads, I will provide enough information to achieve a satisfactory result . It is not rocket science and provided that the designer observes a few rules , the end result will be rewarding. It may be a design that you've had in the back of your mind for some time, that ticks all the boxes. However, the success of this project will be indicated by your response and feedback to the idea. It could work hand in hand with Kennyglide and his Corflute projects, I'm sure Ken would enjoy being involved and offering a helping hand.

Brian C

[AceTutor]

However, the success of this project will be indicated by your response and feedback to the idea.
Brian  C

Hi Brian

Count me in! Even though I am at a distance Bunnings is within walking distance of where I am domiciled.

Cheers JR

[Brian Clarey]

First step in design is to is to draw up a list specifications. Wing span/chord, model usage, expected weather conditions, wing loading etc. 
 From the following attachment, it will be seen that most dimensions are derived from percentages of the  root chord.