David Swanson wrote:
... can anyone tell me how many layers of fiberglass Eduardo used on his fuselage? ========== David, Hi. I looked at Eduardos (amazing!) site and I think he is using 3 layers of glass on the outside (not specified in the text) and 3 layers of glass on the inside (specified in the text). Plus, he is adding an additional layer when he inserts the spars (specified in the text). What I dont find on his website is the type of glass he is using (ie. E-glass, S-glass, etc.), the style (ie. BID, UNI, Bi-axial, etc.), the weave (ie. normal, twill, etc.), the weight (ie. 5.7 oz, 10 oz, etc.), nor the orientation (ie. 90-0-90, 45-90-45, etc.). These are all VERY critical factors to consider when designing an aircraft with fiberglass. And it isnt as easy as it appears. There is a LOT of thought and calculation involved to get to the end result. This is not where you want to use TLAR & GEFKR engineering (That-Looks-About-Right & Good-Enough-For-KR). ;-) Eduardo does have a disclaimer as to why he doesnt publish these numbers: he is experimenting and hasnt finalized his conclusion with actual results from his (flight) experiment. (Im only the messenger, so dont shoot me!) ;-) Regards, Albert Pecoraro ========== Please note: I do not specify the quantity, location (on the aircraft), or orientation of the fiberglass cloth(s) that I have used in the laminations, and since this is a unique (single) design and has not yet been proven/tested in flight conditions, I consider that publishing this information may be taken as a reference (by someone else) to build another airplane in a similar fashion (ie. using similar construction techniques). Being that the structural resistance/integrity of this fuselage is determined in large part by this material, I do not believe/feel that this information should be presented until I can confirm in real (actual) conditions that the calculations that I come up with in the end (ie. during flight testing) are correct and that the construction of this aircraft using this technique is completely safe for flight. Nota: no especifico cual es la cantidad, ubicación y orientación de telas de vidrio que he utilizado para el laminado, ya que como este es un diseño propio y todavía no fue probado en condiciones de vuelo, considero que al publicar estos datos, pueden ser tomados como referencia para otra construcción similar. Siendo que la resistencia estructural de este fuselaje esta determinada en un gran porcentaje por este material no creo conveniente dar a conocer estos datos hasta que confirme en condiciones reales, que los cálculos realizados a tal fin son correctos y la construcción del mismo, utilizando esta técnica es completamente segura para el vuelo.
