GDL-88 opinions

When there are 2020 compliant options on the market that weigh in at 60 gms, there's no way I would install one at almost 4 lbs. Bought an 88 and sold it rather than install it for that reason after realizing its heft. Of course my ship weighs in at 1,000 lbs empty; weight may be less of an issue for others.
5.2 lbs seems tremendously heavy; wonder why it is.

Is the 60 gram solution 1090 out?
 
Is the 60 gram solution 1090 out?
No, but neither is the solution I am currently running. For those of us who don't fly high or wide, it may be an acceptable solution.
 
@John Collins .. I appreciate you taking the time to post your thoughts; thank you. Obviously, there's more research I need to do regarding the way ADSB-in works from a technological standpoint and I'm glad you've opened my eyes to some of the differences and advantages in a panel mount system.
Having said that, for the first fifteen years of my flying life, the only traffic info I had was my eyes and flight following. Now, I have those same tools, plus a portable adsb-in that, coupled with iFly or FltPlan Go on a tablet, shows me traffic including it's altitude /and or altitude delta from me, location, speed, and course. iFly also shows the traffic in 3D on an EFIS display, and has popup traffic warnings for which I can set thresholds as well as audio annuniators. That's a QUANTUM leap forward, for less than $200, in what I had before. That's just the traffic side. The weather features, GPS/EFIS/emergency AHRS backup attitude indicator, and all that other stuff is there too, and icing on the cake.

I question that if flying with a portable for ADSB-in makes one "fat, dumb, and happy," and that you can only remove the "dumb" part by spending $5000 or more on a Lynx 9000 or other mega buck panel device(s) that include ADSB-in, then prior to ADSB-in we ALL must have been INCREDIBLY stupid. I am very happy, but not fat or dumb. I know you weren't actually calling anyone who used a portable adsb-in "dumb," (at least I hope not), but were rather pointing out, as I asked, what the advantages were of panel mount stuff over a portable. I believe you may have understated the capabilities of what some efb/portable combinations have, but your comments about reception especially are very helpful.

Thanks again.
 
How you equip for ADS-B depends a lot on what you currently have in the panel, and its projected replacement schedule. In my case, I had an ancient Narco AT-50A and was looking at meeting the 2020 mandate as well as thinking about modernizing my transponder. Adding a UAT add-on solution like a GDL-88 or Uavionix tail beacon (when and if available) while relying on an AT-50 transponder into the future looked like a loser proposition. Plus that solution would not provide integration with the GNS-430 or provide for ADS-B in for the EFB. Given all those needs, and preferring not to increase cockpit clutter, the NGT-9000 or GTX345 looked like the best options. I got a really good deal on the NGT-9000, and its wifi module allows for multiple EFB connections--one for me, one for the copilot so we can both have our own screens. Sweet!

It pays to think a bit about your future panel strategy before pulling the trigger on ADS-B compliance, so you don't wind up backtracking in the future. I'm happy with my personal decision because I can see an IFD440 in my future (or the next GNS-430 plugin compatible unit) when the GNS-430 becomes obsolescent, and the NGT-9000 will be compatible. At some point in the future, I have to decide what to do with my aging Terra NAV and COM units. For now, they work, but they are not likely repairable.
 
How do you know you are receiving from the one and only one tower that is up linking your nearby TISB traffic?.

How would you know if any of it is dead? Never seen a NOTAM for “the link between TIS-B and the UAT transmitter isn’t working today...”

But honestly, without continuous ack/nak and a display in cockpit that the path isn’t working, and should be at this location and altitude, nobody will know when it’s dead, in near real-time.

Let alone NOTAMs.

Fiber cut between the UAT tower site and the data center? I’ll never know in the cockpit that FIS-B data is missing from the uplink.
 
What one wants with ADS-B In is to get a usable alert if there is traffic detected nearby that represents a collision threat. Each tower that is assigned to transmit TISB traffic continuously updlinks the list of client aircraft for whom it is providing the TISB service. If your aircraft is not on the list, then traffic nearby your location is not being uplinked or you are not receiving from that tower. The list is repeated such that it should be received by a client aircraft within 20 seconds. The intent of this is to provide the pilot with an indication they are inside a TISB service volume and continuing to receive the TISB service for their specific aircraft.

Since any TISB traffic broadcast by any tower can be received as long as the signal is adequate, this often means you will be receiving TISB for tens or in some cases hundreds of aircraft targets and yet none of them may be relevant to the airspace surrounding your aircraft at your altitude, which in the end is what you care about.
 
I question that if flying with a portable for ADSB-in makes one "fat, dumb, and happy," and that you can only remove the "dumb" part by spending $5000 or more on a Lynx 9000 or other mega buck panel device(s) that include ADSB-in, then prior to ADSB-in we ALL must have been INCREDIBLY stupid.

I am very happy, but not fat or dumb. I know you weren't actually calling anyone who used a portable adsb-in "dumb," (at least I hope not), but were rather pointing out, as I asked, what the advantages were of panel mount stuff over a portable. I believe you may have understated the capabilities of what some efb/portable combinations have, but your comments about reception especially are very helpful.

Thanks again.

I used the idiom "fat dumb and happy" to mean blissfully unaware of the truth of the situation, leading to a false sense of security. In my case, I am fat. :)
 
Thanks to all who replied, especially to @John Collins for his explanation of the technical reasons why traffic in the panel is much preferable to portable solutions. I have to discuss with my shop re: the reliability of transponder command the the 480 and the 345R, but I'm inclined to go that route if it's workable, in spite of the higher price.
 
Thanks to all who replied, especially to @John Collins for his explanation of the technical reasons why traffic in the panel is much preferable to portable solutions. I have to discuss with my shop re: the reliability of transponder command the the 480 and the 345R, but I'm inclined to go that route if it's workable, in spite of the higher price.

Getting certified ADS-B in is worth the extra. BTW the GTX-345 is less expensive than the 345R, and it can also be remotely operated though any Garmin MFD/PFD set-up that can interoperate with the 345R; except maybe the G1000.

Besure to consider the inexpensive OAT option to see Density altitude and temp on the 345 display if you go that route. The GDL-88 is a legacy product who's time has past.
 
Getting certified ADS-B in is worth the extra. BTW the GTX-345 is less expensive than the 345R, and it can also be remotely operated though any Garmin MFD/PFD set-up that can interoperate with the 345R; except maybe the G1000.
Reference? According to Garmin's brochures, they both list for $4995.

Besure to consider the inexpensive OAT option to see Density altitude and temp on the 345 display if you go that route.
Will discuss this with my shop... thanks.
 
Reference? According to Garmin's brochures, they both list for $4995.

Why can't a product can be obsolete while it's still available for sale? Who would buy a GDL-88 when nominally more get a new GTX-345, both a pound lighter and more capable.
 
Why can't a product can be obsolete while it's still available for sale? Who would buy a GDL-88 when nominally more get a new GTX-345, both a pound lighter and more capable.
??? :confused2:

My question was about the 345 vs. 345R, not the GDL-88. You said the 345 was cheaper than the 345R, but according to Garmin the list price is the same.

If the list price is the same, the only advantage I see to the 345 is the panel display, but the only place I could install it in my panel is on the extreme right, after pulling out an old secondary GPS (a Trimble) that's no longer supported.
 
??? :confused2:

My question was about the 345 vs. 345R, not the GDL-88. You said the 345 was cheaper than the 345R, but according to Garmin the list price is the same.

If the list price is the same, the only advantage I see to the 345 is the panel display, but the only place I could install it in my panel is on the extreme right, after pulling out an old secondary GPS (a Trimble) that's no longer supported.


FWIW, my Cardinal has a 345 way over on the right, I never look at it anymore, its remote controlled from the GTN in the middle. That said, some of my passengers entering codes on the GTX, I always use the GTN.
 
??? :confused2:

My question was about the 345 vs. 345R, not the GDL-88. You said the 345 was cheaper than the 345R, but according to Garmin the list price is the same.

If the list price is the same, the only advantage I see to the 345 is the panel display, but the only place I could install it in my panel is on the extreme right, after pulling out an old secondary GPS (a Trimble) that's no longer supported.

I'm glad Garmin finally normalized the 345 & 345R prices. Never understood why the R model was $400 more expensive.
 
What I really don't like about the R is if your control head fails you don't have any transponder control anymore.

Some of these radios controlling the transponder may not be repairable anymore.

If buying used replacements for an unrepairable unit software level issues may arise.

I
 
The R was on some sort of overstock sale when we installed ours and our GTN. Remote was cheaper.

With the amount of panel space we have, we were advised against it.

In our case, if the GTN failed we could need a waiver to fly in various airspace since we live under a Mode C veil. With the front panel controls, you just keep flying. Even to the avionics shop.

Wasn’t worth the price difference and hassle unless there really wasn’t any room to do anything else but a remote.
 
What I really don't like about the R is if your control head fails you don't have any transponder control anymore.

Some of these radios controlling the transponder may not be repairable anymore.

If buying used replacements for an unrepairable unit software level issues may arise.

I
That's a good point... my controller is a 480, which Garmin recently announced they will no longer service. So straight 345 it is, then... better way over on the right than in the tailcone. I will ask the shop to pull the Trimble.
 
Thanks to all who replied, especially to @John Collins for his explanation of the technical reasons why traffic in the panel is much preferable to portable solutions. I have to discuss with my shop re: the reliability of transponder command the the 480 and the 345R, but I'm inclined to go that route if it's workable, in spite of the higher price.
thats one of my options and my avionics guy sayz that will work
 
That's a good point... my controller is a 480, which Garmin recently announced they will no longer service. So straight 345 it is, then... better way over on the right than in the tailcone. I will ask the shop to pull the Trimble.
usually the install cost is more for the R because they will take the side out to run wires, since you have GDL-90 in the tail, you can reuse the wires (i think), having said all that, i am thinking of 345 and adding a OAT probe. if i am spending 5K i want to see it and have the option of pushing buttons on it
 
usually the install cost is more for the R because they will take the side out to run wires, since you have GDL-90 in the tail, you can reuse the wires (i think), having said all that, i am thinking of 345 and adding a OAT probe. if i am spending 5K i want to see it and have the option of pushing buttons on it
Yeah. I'm not sure either whether the wires can be reused for the 345R the same way they can for the GDL-88 (not sure whether the interfaces are the same), but the estimate I got for the 345R had the same labor costs as for the 88. I won't be able to discuss this further with them for a few days, since my avionics guy just emailed me to say he's in Kansas this week and won't be back until next week.

Does the 345 need its own OAT probe, or can it interface with the JPI probe (I have an EDM-700)? Density altitude calculated and displayed would be nice, but if it's a major additional expense I'm not sure it is really worth it.
 
Yeah. I'm not sure either whether the wires can be reused for the 345R the same way they can for the GDL-88 (not sure whether the interfaces are the same), but the estimate I got for the 345R had the same labor costs as for the 88. I won't be able to discuss this further with them for a few days, since my avionics guy just emailed me to say he's in Kansas this week and won't be back until next week.

Does the 345 need its own OAT probe, or can it interface with the JPI probe (I have an EDM-700)? Density altitude calculated and displayed would be nice, but if it's a major additional expense I'm not sure it is really worth it.

I have the JPI probe as well and just installed another probe for G5, they can’t splice it. Probe costs about 83, from Davtron, install it in a inspection plate little away from the wing root. My install for the probe was probably an hour or so
 
I have the JPI probe as well and just installed another probe for G5, they can’t splice it. Probe costs about 83, from Davtron, install it in a inspection plate little away from the wing root. My install for the probe was probably an hour or so

Same with my set-up. Paid $95 for the probe and an hour labor with OAT mounted to inspection plate near wing root.
 
I have the JPI probe as well and just installed another probe for G5, they can’t splice it. Probe costs about 83, from Davtron, install it in a inspection plate little away from the wing root. My install for the probe was probably an hour or so

Same with my set-up. Paid $95 for the probe and an hour labor with OAT mounted to inspection plate near wing root.

A thermistor and some wire for almost $100.

I’m really in the wrong business. LOL.
 
IMHO there is no point to adding a temp probe to a GTX. I'm sure I'd never look at it. Then again, I'm a flatlander.

That being said I added one for a Davtron Clock right before the Garmin G5 displays OAT interface was announced (grr....) IDK if I wanna add that G5 temp option or just leave it.
 
IMHO there is no point to adding a temp probe to a GTX. I'm sure I'd never look at it. Then again, I'm a flatlander.

That being said I added one for a Davtron Clock right before the Garmin G5 displays OAT interface was announced (grr....) IDK if I wanna add that G5 temp option or just leave it.
Even for flat landers. I was in southern South Dakota last June with 7000' density altitude on 1500' MSL field. It was a scorching day. Also flying 11,500 in So Cal my friend and I were both getting a slight headache. Glanced at the GTX-345 and saw density altitude was 13,700. We adjusted by descending.
 
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