Alternative 4 is a variation of Alternative 2. Alternative 4 would alleviate training shortfalls and address evolving training needs by implementing the same proposed modifications as described for Alternative 2, except that supersonic operations would be authorized down to 10,000 feet above ground level (AGL) in Tombstone, Outlaw, Jackal, Morenci, and Reserve MOAs instead of 5,000 feet AGL proposed under Alternative 2. While this option would not fully optimize the airspace for supersonic operations, lowering the authorized altitude would improve the current capabilities. The other proposed changes would be the same as Alternative 2.
Please review the Summary of Alternatives by Airspace to obtain more details on how these proposed changes affect each MOA.