Garmins new ads B transciever GDL 88

[davidsguerra]

looks like Garmin has a new ADS B device. its a dual band reciever and a 978 mhz out. (UAT)

https://buy.garmin.com/shop/shop.do?cID=272&pID=63471

looks like they have a portable version coming out too.

no compatibility guide yet. pricepoint isnt TOO bad.

for aircraft that can go into class A it doesnt make much sense to get a UAT and a 1090ES tponder am i right? why have 2 transponders?  i plan on getting a 1090ES tponder for compliance and an ads b reciever only. any thoughts?

 

 

[Jerry 5TJ]

Yes, if you are going to be in class A you will have to have Mode S with ES (extended squitter) to provide ADS-B traffic compatibility.    The 978 MHz UAT plus transponder with mode A/C is good for those of us who don't venture above 18,000 or outside the USA.  Current Mode S ES transponders are not necessarily fully compliant with the ADS-B but upgrades are likely to be firmware only. 

As for why have both?  Mode S ES won't provide airborne weather, only traffic, due to congestion in the interrogator uplink at 1090 MHz.   UAT will also provide the FIS weather products.   So, yes, you will probably want both if you go above FL180.  Or you can stay with XM weather as long as that FIS subscription service is available.

Keep in mind you also need a precision GPS source for both the Mode S ES transponder and the UAT, but you'll probably have that in the panel anyway by 2020 when all this becomes mandatory. 

 

[N33GG]

I bet the requirements will change several times before 2020 gets here.  I think I will drag my feet...

[aviatoreb]

Quote: N6719N

I bet the requirements will change several times before 2020 gets here.  I think I will drag my feet...

[N33GG]

So that's where they got the idea for Cirrus!

[davidsguerra]

but if you have a 978mhz reciever  and an 1098 ES mode S you should be able to get FIS-B and TIS-B right? right now  I get FIS-B and some TIS-B on my adsB reciever (skyradar)

IIRC the GTX 330ES will display TIS-B but doesnt not recieve FIS-B.if they would make it recieve 978 mhz it would be a great upgrade.

Trig Avionics claims adsB mandate compliance with their TT-21 and TT31 mode S tranponders. interestingly enough they did the certification in a Mooney.

some one please correct me if i am wrong but why do i need a 978mhz transmitter and a 1098ES transmitter? wouldnt a 1098ES transponder and a 978mhz reciever be sufficient to get TIS-B/FIS-B and be compliant ?

[davidsguerra]

http://www.airtrafficmanagement.net/2012/07/garmin-enhances-adsb-offering/

a good article with some info not on the website.  $3995 msrp. Q4 for STC??? freeflight rangr stc should be finished soon; they are probably are waiting to announce it at oshkosh. says it will be compatible with most mode C transponders as a control head. thats better than the Rangr.

 

[Jerry 5TJ]

 

[Piloto]

One of the main reasons to keep a 1090MHz transponder on your plane is TCAS. TCAS only works on 1090MHz so if you do not have it you will be invisible to TCAS equipped planes like all the airliners. So you will not be allowed to share the same airspace as those with 1090MHz equipped transponders. You can not coordinate traffic collision conflicts (RA) either by ADS-B 978 or ADS-B 1090MHz. Collision conflicts can only be resolved via plane to plane with Mode S or Mode C transponders (1090MHz). Unlike Mode S and Mode C transponders that can transmit 1000/sec data ADS-B 1090MHz ES message is only 1/sec. This is too slow for TCAS. This is why ADS-B/UAT has no sense for the airlines. Not to mention that in South America, the Bahamas and the rest of the world ADS-B is not mandated so you will need a traditional TCAS system to detect traffic.

As for weather I have yet to see something more reliable and greater coverage than XM or WSI. With these satellite based systems I am confident that the system works before engine start. And I can tell while taxing what heading to take to avoid the approaching storm. With UAT\WX I have to be at least 1500feet and within coverage to find out if the thing works and face the posibility of penetrating the approaching storm with no wx data. Not to mention that the weather update delays via UAT are much greater than those mentioned on the recent NTSB report. UAT\WX 978MHz uplink data string can be easily corrupted by the onboard DME, transponder or TCAS causing missing wx slices or wx delays to refresh the corrupted strings. Just imagine an airliner needing to return back to land because they just found out that their UAT\WX is not working. This is why the airlines are not going for it. With XM or WSI you do not have any of the above problems.

With a UAT ground infracstructure more expensive and complex to maintain than Loran C I do not see how it can be justified. Particulary when the population sector it serves is no more than 100,000 GA planes vs millions of boats and planes that Loran C served internationally. I wonder how long the FAA will support the UAT ground infrastructure since it does not serve the general public that flies on airlines without it.

José

 

 

[DGates]

Quote: davidsguerra

looks like Garmin has a new ADS B device. its a dual band reciever and a 978 mhz out. (UAT)

https://buy.garmin.com/shop/shop.do?cID=272&pID=63471

looks like they have a portable version coming out too.

no compatibility guide yet. pricepoint isnt TOO bad.

for aircraft that can go into class A it doesnt make much sense to get a UAT and a 1090ES tponder am i right? why have 2 transponders? i plan on getting a 1090ES tponder for compliance and an ads b reciever only. any thoughts?

 

 

[Jerry 5TJ]

Quote: davidsguerra

some one please correct me if i am wrong but why do i need a 978mhz transmitter and a 1098ES transmitter? wouldnt a 1098ES transponder and a 978mhz reciever be sufficient to get TIS-B/FIS-B and be compliant ?

[davidsguerra]

I was wondering what would be the benefits of a TAS system vs ADS-b with TIS-B? could someone please educate me because i was considering  a TAS but I wasnt sure if it was worth the money. i live in Florida so we get good ADS-B coverage most of the time.

to me it would be too confusing to have 2 transponders. which one would I enter the squawk code? I am considering the navworx reciever and a trig transponder.