Successful?
1. In Military terms - Huey
2. In providing basic training ppl/h and military - H300
3. As a small working machine - B206 series
4. As an attack beast - Apache
5. As a medium sized working machine - S76
6. As a rugged hard worker - Alouette
7. As a SAR - S61
8. As a beautiful design - B222/230/430
9. As a logging/fire fighter - Kamov
10, As a heavy lifter - Mil
Successful does't mean the best but due to it's design and functionallity it has shown a creditable status above others in the group.