A Lancair 360's alternator failed at night. After shedding electrical load the pilot continued to the home airport. In communication with ATC; but after a navigation error; the pilot flew into military airspace.

Narrative

The flight under VFR with ATC flight following in my Lancair 360 became abnormal when the aircraft's alternator failed. When recycling the alternator switch did not resolve the problem I shed the electrical load on the aircraft as much as possible; including turning off my GPS and VOR receivers. I was less than 30 minutes from my destination and home airport; so decided to continue to this airport on battery power and navigating at night via pilotage. Once I was switched to the TRACON; I notified them of my equipment failure and asked them to notify the Control Tower at my destination in case I lost radio communication capability before landing. I was given a clearance into the Class B; direct a prominent navigation point and to descend to 3;500 FT. I was instructed to maintain 3;500 FT until navigation point at which time I could descend for the airport. I began to feel like the Controller was late in giving me a frequency change to Tower; because I felt I was over the point; so announced to the TRACON that I had the airport in sight. The TRACON told me that my altitude restriction was canceled and to contact Tower. I established two-way radio communications with the Tower; but did not receive my approach instructions right away. The Tower Controller then cleared me to enter a right downwind for the only runway available for night operations. I was expecting a left downwind entry; so turned northeast to fly on the north side of what I thought was the airport. Soon thereafter; the Tower asked if I was flying north; which I answered in the affirmative. They told me to immediately fly south and asked if I had the airport in sight. I then realized that I was north of the navigation point and had turned east too soon; putting me in military airspace just to the north of the airport. When I told the TRACON that I had the airport in sight; I now know that it was a military airport that I saw. The Tower turned up the runway lights to help me locate the airport. Once I realized my error I entered a right downwind and landed without further incident. While I have flown in this area for more than 15 years; the distraction of knowing that I was on limited battery power with an inoperative alternator light flashing in my dark cockpit lead me to misidentify a common landmark on my arrival and descent into my home base airport.