Need advice on GPS purchase

[310]

I need advice from those that have used Garmins, UPS Tech, King-Bendix and any IFR enroute and approach GPS/Comm with pros and cons. With Garmin I am looking at the "300" and "250" models- not the 430/530. Also and info about websites that have comparison info. Thanks.

 

[jmc]

310,

About 3 years ago, I went thru the same selection process that you seem to be going thru now. With so many choices and such strong opinions by the users of this equipment it can be difficult to make a decision.

I tried to rate the units with regard to the following issues
Features, ease of use, cost, support, and compatiblity

The three units you mentioned are all good boxes but with regard to cost I believe you can eliminate the King unit. So now you have two choices. UPS or Garmin.

After many hours of use and evaluation, I feel very comfortable with the UPS GX50 I installed in my plane. The small moving map seems adequate for excellent situational awareness. One weak point is that the entire approach procedure is not shown on the Moving Map. The course from the FAF is shown (no procedure turn, Hold or missed approach procedure) to the Missed approach point.

If you are not considering the 430 or 530, and in the future you want to add a MFD (multi function display) for a better moving map, approach procedures, weather, traffic, terrain.... then the UPS unit will be more compatible with the UPS MX20 MFD than the Garmin unit will be with the other MFDs available.

Auto Pilot connection is another issue to investigate. My unit is coupled to my Auto pilot. The Auto Pilot connection does not get much use because the GPS signal seems to update too often and the Auto Pilot continuously wanders back and forth over the intended course. I am told that the newer Auto Pilots have a GPS steer function that minimizes this (GPSS). Also, in actual conditions I feel more comfortable hand flying the approaches so it gets no use there. Enroute I use the Auto Pilot to follow the heading bug and monitor the track on the GPS.

The trickiest part of the operation is approaches with missed approach procedures which require you to track outbound on a given Radial .... It gets pretty busy with the transition and mashing buttons to get the GPS to track a VOR radial to an intersection and then prepare for the hold. As a result, If an airport has a VOR approach with a GPS Overlay, I'll ask for the VOR and monitor the approach on the GPS. It just simplifies things if conditions are marginal. This is why I did not get the GPS unit with the COMM feature. I kept two comms and two nav recievers in the panel and am very glad I did.

The last point for consideration is WAAS compatiblity. I know that Garmin is providing WAAS software patches for the 400 and 500 series units but I don't know about the 200 and 300 series units. UPS has in the past said that software patches would not be possible for the GX units, but I don't know the current position. WAAS would be a very significant issue for me if I was buying now. It will be very nice to have lower mins and glideslope information on GPS approaches. This in itself would make me request the GPS approach every time! I have heard that WAAS availablity is ahead of schedule and could be here by June 2003.

If I were doing it again I would make the same choices, but I would be sure it was WAAS ready. Also I am thinking of adding the MX20.

I hope this was helpful and not to long winded.

Email me if you have any questions
[email protected]