Monday, October 31, 2011

External link: Article about Flying wings

If you are into flying wings like me, this PowerPoint slideset might interest you. It compares the basics of conventional airliner and flying wing airliner. Much bigger planes in other words, than my interest area. However, some of the pros and cons findings for each configuration also apply for the small version. Not all though as the starting point does not have engine nacelles and engines sticking out of the wing. http://www.engbrasil.eng.br/index_arquivos/ap23.pdf I haven't done yet comparison for the wetted area of a flying wing compared to a sailplane like structure. Logic tells that the flying wing in this size category might have more wetted area. But I am not sure. I need to design both and then measure the wetted area of both and compare. I am not a big fan of wing twist and the amount of wing twist on PUL-10 causes me shivers (wing tip twisted 10 degrees). That can't be good for cruise, simply can not. Ten degrees is insane amount of twist - on cruise the tips are on negative angle of attack and cause a lots of negative lift. The wing tips act as rather poor tails this way - it is very short coupled and if you have tail deflected that much on that close, the wing center section will need to lift also the negative lift of the tips which will make the plane to perform poorer. I am quite sure that a flying wing should be made stable without that much twist. I have a related idea for a flying wing: - one problem with flying wing is that flaps can not be used - what if you had small trim tails that look like the ones in SpaceShipOne. When flaps would be down, the trim tail, would cause opposing pitching moment to negate the pitching moment of the flap - The elevator control otherwise would be like on a flying wing, with elevons. - I haven't tried this out yet but it can be tested with RC model.

Wednesday, October 12, 2011

Short note: Electric motors for hybrid or electric aircraft

The Joby Motors seems to have good enough KV-values for running slow turning props (especially JM2S and JM2):
http://www.jobymotors.com/public/views/pages/products.php

Electric Lazair uses these motors. Standard windings are available for up to 700 volt system!

Thursday, October 6, 2011

OT News and Comment from Author: This is a sad day - Steve Jobs has died

I was shocked to read the bad news about Steve Jobs. He is surely one of the few persons in the Wolrd that have inspired me a lot. The World has now lost one of the guiding lights and Steve is no more.

His legacy should not die. In whatever you do (his wisdom is not limited to computers and mobile phones, but also apply for aircraft, space technology and everywhere) - live your each day like it was your last day. Ask yourself, that what you would want to give to the world if this was your last day. Don't tolerate being mediocre, but create something that will change the World.

Steve is one of the rare people who had realized that statements like "maybe after 100 years we have the technology..." are simply failed logic. It does not take any period of time for something that would be like given from somebody. Nothing is given. Everybody has to work hard to make the dreams come true. There are no dreams coming true, if you don't work for what you dream for. This after 100 years never comes if everybody is just waiting for the time to make its work. Time will not make its work, it is the passionate people who do it. Stop dreaming, do what you want to do, and show to the World that you can do it. Do what you are passionate about, it is the passion that will change the world. Even if it is something market does not even consider to exist, but if you are passionate about it and find others who are too, just do it.

My sincere respect to Steve Jobs and my condolences to the family and fans world wide. But please everybody make his legacy to live on. Stay foolish. Stay hungry.