definition of DALGT in notam

I looked through the FAR's and there was no definition of "daylight".  However, 91.209 does say that lighted position lights must be used during the period of sunset to sunrise.  Although it's not a very satisfactory answer, I'd say the conservative approach (no pun) would be to apply that same logic to this NOTAM. 

If you really want clarification, you could write a note to FAA Legal, but that's always fraught with potential complications - or as one FAA legal counsel once told me, "You may not like the answer you get if you ask."

Bob,

Thanks for your reply.  I found several reference in the FAR's which almost answer my question, but not quite.  One is FAR 61.57 (night currency) which uses "1 hour after sunset and 1 hour before sunrise".  FAR 61.109 (aeronautical experience) and FAR 91.151 (fuel) both refer to "night".  Lastly, FAR 91.157 (special VFR) and FAR 91.209 (Lights) as you mentioned refer to "sunrise and sunset".

I quess that it will just remain a question unanswered.

Hobby Stevens, N41HS, RV6

That's my point:  daylight is not specifically defined.  If you were one of my students, the "best" answer I could give (e.g. most conservative) without an interpretation would be that daylight is from sunrise to sunset.  Or, to put it another way, is it worth the hassle if you land 10 minutes after sunset and get violated for it and then have to prove your case?  IMHO, prob'ly not...