From: nws@stout.atd.ucar.edu (Eddie Roberts (The National Weather Service))
Subject: SUMMARY :  abbreviations defined
Organization: Atmospheric Technology Division/NCAR Boulder, CO
Date: Tue, 1 Sep 1992 16:28:00 GMT



Thanks to those that responded to my post about
skydiving/aviation abbreviations.  I've summarized most
of the responses without any editing.  I decided to take out
some opinions on the pros and cons of "throw-out" vs.
"pull-out" pilot chute since it wasn't my intention to
restart a flame war.

        Thanks again....
               Eddie




CTAF        Common Traffic Advisory Frequency -
----
            1.) The "standard" radio frequency used at a particular
                airport.  Each airport has a particular CTAF
                (although some airports may have the same CTAF because
                they're far enough apart).

            2.) aka. UNICOM, used by planes at uncontrolled fields to
                notify others in the area of their intentions.


ATC         Air Traffic Control -
---
            1.) Either a control tower (in charge of a particular airport)
                or an "approach" or "center" controller (in charge of
                a chunk of airspace).  Remember, not all airports have
                control towers.

            2.) FAA employess concerned with the coordination and separation
                of airplanes in accordance with the appropriate FARs.


BSR         Basic Safety Requirements/Regulations -
---
            1.) The basic rules created by the USPA covering student
                operations at USPA member drop zones. Most are followed
                by ALL drop zones.

            2.) The set of rules laid down by the USPA by which all
                members and affiliates are expected to comply.  The USPA
                is not a government organization, and therefore, the
                BSRs are not law.

FAR         Federal Aviation Regulations -
---
            1.) The FAA is part of the government, and so, FARs *are* law.



GA          General Aviation
--


IFR         Instrument Flight Rules -
---
            1.) The set of rules obeyed by pilots who are flying
                "on instruments."

            2.) Governs all flight above 18K and flight without aid
                of outside visual reference, planes  can fly under IFR
                in good weather, too.

VFR         Visual Flight Rules -
---
            1.) The set of rules obeyed by pilots who are flying
                by visual references.

            2.) Good weather, good visibility, "Piper Cub" flying so to
                speak, what a newly licensed Private Pilot flys in and
                (to the best of my knowledge) what skydivers jump in.

           IFR and VFR are also used to describe weather, as in "the weather
           was IFR" meaning it was a bad day to fly.  This is actually a
           misnomer.  The words to describe weather are IMC and VMC
           (Instrument- or Visual- Meteorological Conditions).

           VFR/IFR = how a pilot is flying.
           VMC/IMC = what kind of weather there is.


The difference between a throw-away pilot-chute and a pull-out pilot chute.
---------------------------------------------------------------------------

Explanation 1.

They are both pilot chute deployments of the main.  A throw out is
the type that you place in the wind stream and let the wind pull
the pin (it has a curved pin).  A pull out is one where you physically
pull the pin (straight pin) and deploy the pilot chute in one motion.
After that they're both the same... the pilot chute pulls out
everything else.  It's a religous matter as to which is better
(sort of like emacs vs vi).


Explanation 2.

	Commonly called "throw-outs" vs "pull-outs".

        With a "throw-out", the pilot chute is packed in a pocket
	outside the main container (generally on the legstrap).
	The pilot chute bridle is attached to the closing pin
	on the main container.  The bridle continues past the pin
	into the container and is attached to the canopy as normal.

        On deployment, the pilot chute first pulls the main closing
	pin, then continues on to deploy the main canopy.

	A "pull out" pilot chute, however, is packed inside the
	main container with the main.  A short bridle extends
	from the pilot chute to a small handle outside the closed 
	main container.  This short bridle is attached to the
	main closing pin and to a small handle (or the "pud").

	At deployment, the jumper grasps the pud, and extracts 
	the main closing pin at the same time as they deploy the
	pilot chute.

        ...... opinion deleted ......

Explanation 3.

        A throw-away pilot chute is kept in a pouch on the right
        leg strap.  The pilot chute has a handle at the top which
        sticks out of the pouch when folded up to give you something
        to grab on to.  The pilot chute has a bridal attached, which
        is routed to the main container and connected to the bag.
        The bridal also has a pin attached to it (curved) about 12"
        from the bag which is used to hold the main container closed.

        To deploy a throw-out/away, you simply pull it out of the pouch
        and throw it into the air.  The pilot chute inflates, pulls the
        pin out of the closing loop, and then pulls the bag out of the
        container, releasing the lines from their stowes.

        A pull-out pilot chute is similar but there are some key
        differences.  A pull-out has a soft handle (pud - similar
        to a cut-away pud) on the bottom right corner of the container.
        This handle has a short bridal with a closing pin (straight)
        about 12" from the handle. Past the closing pin, the bridal
        attaches to the pilot chute (which is tucked under the flaps
        of the main container) and then to the main bag.

        To deploy a pull out, you simply pull the handle which
        immediatly extracts the pin and releases the pilot chute.
        In the same motion, you throw the pilot chute into the wind
        and the deployment continues just like a throw out.


        ...... opinion deleted ......


Miscellaneous
---------------
               
PP   = Private Pilot
ASEL = Airplane Single Engine Land
IA   = Instrument Airplane
IGI  = Instrument Ground Instructor

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