Kilgore Trout:
There are some installations of aircraft strobe light systems on aircraft wingtips that replace the need for a white tail navigation light
No offense, but I don't know of any!
The STC you linked to mentions a replacement for existing
anti-collision light systems. There's no mention of position lights that I can find. For a lot of reasons it's very unlikely that such a substitution would be allowed. Somebody correct me if I'm wrong. A position light needs to be, and can be, on 100% of the time at night. It's often not safe to do this with a strobe (fog, proximity of other vehicles on ground, etc.)
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freeze3192:
could you legally fly at night with one of the aft facing wingtip position lights INOP?
Unless it's some sort of a redundant installation, no (unless you had some sort of a ferry permit).
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OP:
am having trouble locating the appropriate aircraft lights
Turn the master and position light switches on (only those switches) and walk around the airplane looking for steady white light (s).