This has been partly fixed.
Yes there is a problem and the FAA made them remove 1/3 of the approaches in their database initially. These are apparently going to be reinserted Thursday but the doc you attached Peter is the requirement the FAA needed to permit that.
The problem is somewhat arcane.
As I understand it the situation manifested itself when flyng a temperature compensated approach, and even then only if the pilot changes the “climb to” altitudes in the missed approach sector of the fight plan.
How many people on here fly temperature compensated approaches on their FMS?
But even Collins screw up big time at times
I like the “may turn in the wrong direction” bit 
When I did some research for the Avanti it depended on if the PL21 system had the Collins FMS and transponders and TCAS II. Then the upgrade path was expensive. If it had 3rd party FMS and transponder, then the upgrade path was cheaper. You could just stick a Garmin in there. This assumed it had TCAS I. With II, somehow, they were all expensive, as they were an integrated part of the FMS.
Confusing stuff.
AdamFrisch wrote:
The concerns are with the upgrade path for ADS-B on many of the, let’s say 1990-2017, models years of planes. An integrated PL21 can be a cool $70-100K to upgrade. Whereas if you had a Garmin system, it could be done for maybe $20K. It’s a real issue that will effect values in the coming years.
It has already fully affected value. A non-upgraded one goes for the exact price of the upgrade less. So actually it is a non-issue now.
AdamFrisch wrote:
An integrated PL21 can be a cool $70-100K to upgrade. Whereas if you had a Garmin system, it could be done for maybe $20K.
I have a quote for £30K for an ADSB out upgrade for a 3 year old Proline 21 King Air 250. Not quite as bad as you say, but still silly by light aircraft standards.
From what I’ve heard is that many self made guys come from Garmin planes, but as they step up in aircraft, encounter Pro Line 21’s eventually. And they complain and whine for awhile but then seem to quiet down. In the end many admit that Pro Line is different, but a good system.
The concerns are with the upgrade path for ADS-B on many of the, let’s say 1990-2017, models years of planes. An integrated PL21 can be a cool $70-100K to upgrade. Whereas if you had a Garmin system, it could be done for maybe $20K. It’s a real issue that will effect values in the coming years.
I like Proline 21 a lot more than Garmin, I feel the Rockwell Collins is less pretty graphics but does everything you need. The VNAV functions are excellent as Peter mentioned early in the thread.
But most of all I suspect it’s because I have hundreds of hours on Proline 21 and tens of hours on Garmin.
I think Garmin are winning the orders for commercial reasons.
wigglyamp wrote:
Over 500 Kingairs have been upgraded with G1000. Whilst there is a Proline 21 upgrade available, I doubt there are many that have been done – certainly none have passed our doors.
We fly a KingAir 250 which was brand new around 3 years ago and it has Proline 21. There are 3 King Airs on our field and 2 of the 3 are Proline 21.
I believe they now fit Collins Fusion but they made loads with Proline 21. I can’t believe you’ve never seen one.
Unless you mean you’ve seen lots of Proline 21 King Airs but none that have been upgraded to PL21 from the old EFIS 84 etc?
