Who discovered :

1.Jeep 2.Cell Phone 3.Ball Pen 4.Wrist watch 5.Fan(Machine)

6.Calculator 7.Aeroplane 8.Helicopter 9.Printer 10.Motorcycle

11.Telephone

http://www.google.com/
Contributors to Flight:
http://invention.psychology.msstate....ors/index.html
Personally, It is hard to say who actually invented many things, Inventors are cheated regularly.
I have studied Flight/Early flight for many years.
Chanute, Whitehead, The Lillienthals, and others contributed greatly. Wright Brothers used a book written by Otto Lillienthal, "Bird Flight", Very Informative book on Flight, and Gliding.
I feel Bell gave Curtiss the insight on ailerons, and on a side note The "Step" on Seaplanes and later Speed boats, to break the suction from the water was the idea of Curtiss.
Curtiss and the Wrights fought in Court for years(lawyers and Money would determine), Wilbur would pass on and eventually Orville and Glenn formed The Curtiss Wright Aircraft.
Langly who thought, once an Aircraft was in the air it could fly indefinitely, being pushed by the air and had Major Financial Backing, would try to take credit.
Instead of being referred to as the Wright Brothers, It maybe should say , The Wright Family, as their sister provided much of their financing to accomplish flight.
In 2003, Fellow EAA'ers tried to fly a replica of the Wright Flier and failed. I believe 2 picked for the flight, one a Fighter Pilot and the other a commercial pilot may have been a bad choice as they are used to Hydraulics carrying most of the load. I would have picked a Test Pilot Like Rutan.
To be fair, He had one chance, where the Wrights, slowly learned the feel and control of the craft over time, and since the craft was so different from conventional Modern Flying Machines, He was at a disadvantage. No mater what, it didn't fly 100 years later.
Good Luck on your homework.
Please don't ask about the Telephone. Take Care