Path: utzoo!linus!husc6!cmcl2!rutgers!bellcore!faline!thumper!karn
From: karn@thumper.bellcore.com (Phil R. Karn)
Newsgroups: sci.space.shuttle
Subject: Re: New Schedule
Summary: Lightning protection
Message-ID: <941@thumper.bellcore.com>
Date: 10 Feb 88 18:18:23 GMT
References: <191800003@trsvax> <248@encad.Wichita.NCR.COM>
Organization: Bell Communications Research, Inc
Lines: 22

> Has anyone else observed that this schedule leaves the Discovery sitting out
> exposed to the weather for the bulk of the (often violent) Florida summer
> thunderstorm season? What about the distinct possibility of lightning 
> strikes to the launch complex/vehicle????

Lightning is so common in central Florida that lightning protection has
long been built into the launch pads. That tall white mast you see on
the fixed portion of the shuttle launch tower is a fiberglass (!)
lightning rod. A heavy cable runs from the ground south of the pad
through the pulley and back to ground on the north side of the pad; this
wire is often visible in pad pictures.  This system serves as a
lightning rod. The fiberglass rod ensures that strikes travel through
ground via the wire and not the launch tower itself where they
could induce secondary surges in nearby shutte systems.

As long as it's on the pad, the shuttle is quite safe from lightning
hits. The tower has already withstood several hits with the shuttle on
the pad. The high winds often accompanying thunderstorms are another
matter, and of course the shuttle is not protected from lightning when
it's somewhere on the 3-mile 3-hour trip between VAB and pad.

Phil