Drill Bit Aircraft Tools
Aircraft drill bits are normally 6-inches long rather than jobber drills which are 2 - 3-inches. The reason aircraft drill bits are longer is to provide more control when drilling. The longer drill bits allow the operator to flex the bit in order to move it a small amount in any direction. This is important when drilling out rivets. The longer bit is much easier to move the bit to the center of the rivet.
Another advantage is that spring type drill stops are easier to install and adjust on the longer bits.
The Isham Inc. RV Aircraft Tool Kit includes the required range of 6-inch aircraft drill bits for building the Van's RV airplane. You may check out the complete tool kit at the link above.