[sci.military] Sidewinder !!!

mmm@cup.portal.com (01/02/90)

From: mmm@cup.portal.com
The article I recommended in an earlier posting had an odd technical error.
It had a picture of an early square-finned Sidewinder with three men standing
around looking at.  The caption said that the man on the left later invented
rollerons, which are a simple low-tech mechanism the Sidewinder uses to
inhibit rolling.

A rolleron is a metal disc with grooves near the edges so that it will spin
while the missile is flying (half of the disc is shrouded; half is exposed to
the airstream).  I surmise that they work like little gyroscopes, flexing the
tail fin on which they are mounted if the missile rotates too quickly along
the axis of its flight.  They resist the rolling motion by changing the 
aerodynamics.

Anyhow, the caption doesn't agree with the picture.  It says this guy LATER
invented rollerons, but if so he must have gotten the idea from looking
at the missile in the picture, which quite clearly has rollerons (they're
located on the tail fins, at the corner between the out-board edge and the
trailing edge).

What has me confused is the last photo in the article.  It shows a
Sidewinder being loaded on an F-16, and this missile seems NOT to have
any rollerons.  Could this be an air-to-ground version, or a version
for practice (the article said rollerons were only needed for stability
at high altitude)?

tdrinkar@cosmos.acs.calpoly.edu (Terrell Drinkard) (01/04/90)

From: tdrinkar@cosmos.acs.calpoly.edu (Terrell Drinkard)
In article <12703@cbnews.ATT.COM> mmm@cup.portal.com writes:
>From: mmm@cup.portal.com
>
>What has me confused is the last photo in the article.  It shows a
>Sidewinder being loaded on an F-16, and this missile seems NOT to have
>any rollerons.  Could this be an air-to-ground version, or a version
>for practice (the article said rollerons were only needed for stability
>at high altitude)?

A friend of mine works at the Naval Weapon Center at China Lake and
he has told me a story that I thought I'd pass along:
  A CPO on some aircraft carrier wrote the manufacturer of the
Sidewinder (I forget who) to tell them how much he and his group
appreciated the thoughtful inclusion of little wheels on the tail
fins for dragging the missles about on the flight deck when the
appropriate dollies weren't available.
  There was shortly an ECO (engineering change order) performed to
the sidewinder which shrouded the entire wheel.  A slot on the top
of the fin now leads the flow past the rolleron.

So there you have it.  You can't see the rollerons on the new
Sidewinders because they are completely shrouded to prevent abuse
by the ammo handlers.
 
Terry

Disclaimer et la Signaturo:
Hell no, I'm not responsible for what I say!  If everyone were
responsible for what they said, we'd have had a balanced budget in
1984.

military@cbnews.ATT.COM (William B. Thacker) (01/04/90)

From: att!utzoo!henry
>From: mmm@cup.portal.com
>What has me confused is the last photo in the article.  It shows a
>Sidewinder being loaded on an F-16, and this missile seems NOT to have
>any rollerons.  Could this be an air-to-ground version, or a version
>for practice (the article said rollerons were only needed for stability
>at high altitude)?

As far as I know, all Sidewinders have rollerons.  It might be a practice
dummy.  There are no air-to-ground Sidewinders, with the marginal exception
of Sidearm (which is a small anti-radar missile, a rebuild of an old radar-
guided Sidewinder variant).

                                     Henry Spencer at U of Toronto Zoology
                                 uunet!attcan!utzoo!henry henry@zoo.toronto.edu

mmm@uunet.UU.NET (01/10/90)

From: <ames!ames!claris!portal!cup.portal.com!mmm@uunet.UU.NET>
About an hour ago, I was over at Halted Specialties in Sunnyvale (Silicon
Valley's premier electronics junk shop).  I was surprised to see the IR
detector assembly, including the quartz hemisphere, from the seeker head
of an AIM-9B Sidewinder missile.

They want $180 for it.  I offered to trade 1000 gold-plated edge connectors,
but they refused.  Darn, if only it weren't so expensive, I'd buy it.
It's beautiful.

You can call them at (408) 732-1573.