Timz From United States of America, joined Sep 1999, 6634 posts, RR: 7 Reply 3, posted (13 years 2 months 5 days ago) and read 826 times:
The 4300-ft rule (US only?) refers to simultaneous independent instrument landings. If ATC keeps the aircraft staggered (i.e. not alongside each other) ILS approaches can be flown to closer parallel runways, and of course in clear weather airliners land side-by-side on SFO's runways 28L/R, which are 750 ft center to center. The legal minimum is maybe 700 ft (?).
Iainhol From , joined Dec 1969, posts, RR: Reply 4, posted (13 years 2 months 4 days 21 hours ago) and read 814 times:
At SNA the runways are quite close together between each hold short bar there is barely enough room for a 757. So I would guess it is about 200 feet. With 19L being 75 feet and 19R 150 feet, that makes them very close together.