UNS-1C PPOS holding
 

Anybody know how to program the UNS-1C, when ATC gives you a hold at present position?
Programing a hold over a VOR/NDB or a defined fix is straight-forward; however, how to program it when told to hold at PPOS, is what I'd like to know.
Thanks.

Blimey.........That instruction might wake me up!!
Thank Gawd we don't have that often over this side of the "Pond"!!!
:-)

I may be wrong, but this looks like a sucker bet. I don't think ATC can give you a "Hold at PPOS" instruction... I've never heard it. My opinion is that ATC has to give you a "hold at" position first.

Maybe someone will look it up in TERPS.

FR

The only way that I could think to do it (and I've never heard of this being asked for) is to create a waypoint at present position, and then set up the hold as you normally would. I am flying tomorrow and will try it out and report back with the details.

This is not something I made up; this is a legitimate ATC instruction.

@upontop325, I would be interested in knowing how you set it up. Thanks.

I forget what page it is on, but there is a position hold function that will map your current lat/long position, and allow you to create a user waypoint (if I remember correctly.) From there, I'm pretty sure you could punch that waypoint into the holding page and set it up. Of course the second you press the button, you are already past the waypoint you just created, so you would have to put the aircraft in heading mode and 180 it around the other way while you fiddle around with the holding definition page. Like I said, I am flying tomorrow and will try it out...I'll let you know what I come up with.

Cheers,

Andrew

On the bus its on the hold page, bottom right I think. ie "hold ppos" Just line select and job done!!

From the operator's manual:

Hold at Present Position

From any [NAV] page, select the LSK [2R] to access the Maneuver Page.

http://i1135.photobucket.com/albums/...bpsen/FMS4.jpg

Press LSK [5L], PPOS HOLD.

http://i1135.photobucket.com/albums/...bpsen/FMS1.jpg


The Holding Page is displayed. The hold FIX field is prefilled with present position, PPOSX, where X equals 1-9. Also prefilled is the hold inbound course to the current flight plan track.

http://i1135.photobucket.com/albums/...bpsen/FMS2.jpg

To change the default turn direction, time, distance and entry type, press the adjacent LSK, enter the new value and press [ENTER].

Press LSK [5L], DTO HOLD.
The PPOS hold is positioned 15 seconds ahead of the aircraft along the aircraft’s current track.

http://i1135.photobucket.com/albums/...bpsen/FMS3.jpg

Hmmm I don't remember seeing that option, but I will check tomorrow! That would certainly be the easier way of getting it done.

It's available with software version SCN 803/903 or higher.

@KBPsen, thanks for that!
However, the UNS' that we use don't have the PPOS HOLD option, which is why my question.

@upontop325, I think you are correct. I do recall seeing the HOLD PPOS option in the DATA page, where it shows the Lat/Long. How do we go from there?

Okay, have to check something in the air, but playing around with the box 'o magic this morning in the hangar (SW V 802.4...no PPOS Hold LSK option).

There is a position hold LSK on Nav page 3. I will have to see if it allows you to save this as a user waypoint (I couldn't on the ground, but maybe in the air).

If you have two FMS, I would suggest using #2 to capture the lat long, make note of the aircraft track for inbound leg definition, then go to heading mode and do a 180. From there, go straight to holding definition on FMS #1 and type in some random name (I just typed USER1). If it doesn't already exist, you will be prompted to define it. Type in the lat long that you have held on FMS #2, and then set up the hold as you normally would.

I'll verify this in about 6 hours after I'm done today.

Okay, I tried it out in flight and it worked as I described it...seems like a real pain in the ass though, and I might consider asking if we can just orbit.

So if you were given a hold over present position instruction you would just immediately slow to max holding speed right?

Anything stopping you from hitting HDG, turning outbound and starting a timing? Then let Bloggs program the FMS while you fly - most of them get awfully nervous when not in managed mode ;)