[A proposal for using ultrasonic wave bird flock repellents in aircraft]

thank you very much audioguru and hero999  :D (that's a lot of help)

ahhh.. so those are the reasons why such thing don't exist (it is not feasible to use that technique).

well.. I also have this one idea- (I have not yet made some researches)
it is about "easy file sharing"- copying of files from a flash disk to another without using a computer. Don't know yet if this already exist~ have any ideas?

(oopss.. Sorry- i think this one is out of thread)

again, thank you in advanced! =D

[A proposal for using ultrasonic wave bird flock repellents in aircraft]

      The number of aircraft accidents involving birds are too alarming that's why I have come to an idea to use ultrasonic waves to repel them so that the incident of planes being hit by a flock of bird will not happen. I have done researches about this, but I found out that bird repellents were only installed at home, industries and at the airport T.T
      I might not be the only one to think that the airplanes itself badly need this bird repellent to be installed on the aircraft (not in the airport alone) and I wonder why they (the companies that manufactures these repellents) are not doing it in the first place?
      Could someone give me a hand with this one? I want to propose this topic on our feasibility study. (Need do some researches before i raise this topic on the class)
      Thank you in advanced!  :)

[How can i use a common cathode 7segment as a common anode 7segment display]

??? i have purchased a wrong 7segment part no.

i have bought els411 instead of els422. the nearest electronics store is a 2.5hours trip from my province and i can't afford to travel that far to purchase a common anode led display.

i am currently working on my project using 7447. could i still use my common cathode led display for my project? if yes, how can i do that? please help..