Plagued by doubts whether my wing incidence was as per design in my scratch-builts, and finding purchase of a Robart Incidence Meter at ~ US$ 50 plus shipping from USA unattractive, I decided to build my own
Simple construction, inspired by a Slide Rule Cursor!
(http://s25.postimg.org/i2c20rt4v/20141023_181916.jpg)
(http://s25.postimg.org/jis5wnlfj/20141023_184427.jpg)
(http://s25.postimg.org/hs94v63wf/20141030_182052.jpg)
Operation is simple - level the datum line (in this case, the fuselage top) with a Spirit Level.
Then check the incidence of the horizontal stabilizer and the wing. Here I wanted 1.5 to 2 degrees positive incidence.
Now will figure a way to check down & side thrust of the prime mover axis ;D
Note: the inclinometer is shown sitting on the cursor only for clarity: in use it is on the wooden scale
(http://s25.postimg.org/4k55ohgzj/20141030_181921.jpg)
(http://s25.postimg.org/hzs6dxphb/20141030_182101.jpg)
Sir, What is the purpose of an incidence meter.
is Incidence Meter, not Incidence Motor.
Incidence is the angle of the airplane wing between the reference line (also called the datum line) on the plane's fuselage along its longitudinal axis and the wing's chord. The wing's chord refers to the wing's cross section from the center of the leading edge to the tip of the trailing edge. Just about all kits and properly designed scratch built plans will show this line. If you are building an ARF, you won't have access to this information, but generally it's a straight and level line off of the stabilizer.
http://www.coronarcclub.com/resources/articles/tips-and-tricks/27-using-an-incidence-meter.html (http://www.coronarcclub.com/resources/articles/tips-and-tricks/27-using-an-incidence-meter.html)
@sanjayrai55
Sir, What is the purpose of an incidence motor.
Sir,
Aapke badhiya Hindustani jugaad pe
Hindustani paani pher diya!
Incidence is this. Meter is to measure it.
(http://upload.wikimedia.org/wikipedia/en/archive/0/0e/20090326053927!Aircraft_Angle_of_Incidence_(improved)--1080x660--25Mar2009.jpg)
Quote from: K K Iyer on October 30, 2014, 09:04:32 PM
@sanjayrai55
Sir,
Aapke badhiya Hindustani jugaad pe
Hindustani paani pher diya!
Life aise hi hai sir-ji :D :D :D
interesting please continue
Continue what? It's done and in use ;)
Quote from: sahilkit on October 30, 2014, 09:26:14 PM
interesting please continue
@sahilkit
Please wait for next episode from Sanjay sir at 5am tomorrow.
It'll be called 'Decalage'
@sanjayrai55
Sir,
What we need is an instrument to measure the relative incidence of the wing and tail (since you are already working on thrust line). If only we had a simple method to ensure zero zero wing and tail plus 2 degree downthrust and 1 degree right thrust, half of our trimming problems would be solved.
Hope your hand has recovered enough to test fly this Sunday...
QuoteNow will figure a way to check down & side thrust of the prime mover axis
this is also done :)
What we need is an instrument to measure the relative incidence of the wing and tail (since you are already working on thrust line). If only we had a simple method to ensure zero zero wing and tail plus 2 degree downthrust and 1 degree right thrust, half of our trimming problems would be solved.
Hope your hand has recovered enough to test fly this Sunday...
Relative incidence is easier! Just check tail, then wing, and subtract!
For thrust, put the inclinometer on the motor/engine shaft after levelling the datum line using a spirit level.
My hand recovered enough for me to crash my Zattack last weekend :( It's a write-off
was it a pilot error or equipment failure ?. Sad the model looked very nice
Not too sure. Was flying alone, the model had done some 40 odd sorties with no problem. First flight of the day, 2 weeks ago, Sunday. Took off smoothly, turned around. On the next turn in the far side of the field, suddenly tip-stalled and went into a fatal spin. Speed seemed ok, maybe radio interference. Fuse broke in the middle! Repaired it, the following weekend flew it again. On the 10th landing, the fuse collapsed again just next to the repair.
Making a QB20L to replace it :)