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Old 02-12-2007
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Quote:
Originally Posted by midlifesailor
The technolgies you are talking about stem almost from the dawn of air navigation.
Yes and they will be around a long time too, not that LORAN is the new kid on the block.
Quote:
Originally Posted by midlifesailor
They are are horrendusly expensive to maintain and are rapidly becoming obsolete. NDB's are being phased out as fast as the FAA can make it happen.
Actually, it cost more to remove them than to renew them. The FAA is not phasing them out so very fast, they plan to move them around a bit to improve coverage and reduce them to a minimum. Getting rid of them is not proving so easy, as was thought for many years, as so many procedures are dependent on them as safety nets.

Quote:
Originally Posted by midlifesailor
No commecial aircraft, and fewer and fewer GA aircraft are equipped with an ADF reciever for NDB navigation and DME is also rapidly becoming cost ineffective to maintain in a GA airplane.
Some airlines are specifying new aircraft without ADF but many keep it in case the aircraft is to do service in countries that still require the ICAO minimum aircraft fit. It is also popular with pilots as it can receive sports results, for example. Only upper end GA use DME at all, it really needs an FMS and preferably also inertial sensors. It is still formally the primary en-route navigation means in many countries. With the introduction of PBN, it is likely to be the safety net for GPS.
Quote:
Originally Posted by midlifesailor
VOR navigation will soon follow the path of the four course range and NDB before it.
Not for many years yet, as many procedures rely on VOR as the safety back-up.
Quote:
Originally Posted by midlifesailor
GPS/WAAS/LAAS won't be piled on top of anything in the future. The ground based stuff, including ILS will go away over time.
A long time. The Fed Nav Plan intends to keep ILS at all airports.
Quote:
Originally Posted by midlifesailor
Loran may not be the answer for a back up to GPS, but until we have an answer, I'd argue we should keep the system active.
Currently, studies are being made to add additional constellations to GPS. This might remove the need for ground based navigation aids, but my guess is that air transport will retain DME as a back-up for PBN.
Quote:
Originally Posted by midlifesailor
I'm not sure were you got the idea WAAS was not being used for aviation.
From Rockwell-Collins, Honeywell, Boeing and Airbus. The first two have no orders for WAAS equipped MMRs and latter two say they have no intention of integrating them on their aircraft – because no airlines are requesting WAAS.
Quote:
Originally Posted by midlifesailor
The Big Iron is using it, and Garmin has had one WAAS certified unit on the market for about 3 years and recently got upgrade approval for their top selling GNS400/500 series units.
Name one airline who is WAAS equipped. GARMIN is the only supplier so far and they don’t sell to air transport. Yes, there will be some mini jets equipped.
Quote:
Originally Posted by midlifesailor
As far as ADS-B, Yes, a mandate is comming. Even AOPA supports it. As to UAT vs. 1090ES, that decsion hasn't been made yet, but its shaping up to be both. UAT as proven itself in Alaska under the Capstone project in GA aircraft, but all new airliners are being delivered with 1090ES capabilty. The FAA ground stations will likely be capable of receiving both and the systems will most likely integrate both types. To soften of the sting of the equipment mandate for GA, the FAA is offering traffic and weather data on the UAT uplink.
I hear there is opposition from Boeing, as to get the air to air benefits, airlines will need to carry UAT, in addition to the Mode-S transponders they already carry. Technically, there is an integrity issue occurring too.

Quote:
Originally Posted by midlifesailor
BTW, Multi lat will not be the answer for en route, terminal and approach surveillence. Automated Dependent Surveillence - Broadcast (ADS-B) will. Multi lat will only be part of some surface surveillence systems like ASDE-X, but even that may be quickly supplanted beacause ADS-B works on the ground as well as in the air.
Trilateration is already in use in Europe for en-route surveillance as part of the RVSM programme. There are studies to expand its use. How far they will go is anyone’s guess. There may be a transition issue with surface applications. The Mode-S transponder is usually switched–off when the wheels are on the ground, this is to reduce the airports’ SSR interrogator’s garble problems. UAT would not have that problem.

Quote:
Originally Posted by midlifesailor
As to the succeptablity of GPS to jamming, the FAA is moving towards GPS based CAT II and CAT III approches.
I wish they were, the FAA don’t have more than an R&D program, LAAS has always had funding problems in the FAA and has only survived because of congress support. At the moment Australia is leading the world with the operational installation of LAAS. Fedex may get an operational installation in Memphis too, but just for them.
Quote:
Originally Posted by midlifesailor
A jamming event would not need to be widespread or prolonged to result in a catastophic event with an aircraft like an A380 in a zero zero landing situation. An ADS-B system that was able to use either GPS or Loran for its postional data would require both to be jammed at the same time, which would at lest make it a more difficult propostion.
LORAN has nowhere near the integrity required for landing aircraft. If you are worried about jamming, worry about the existing aids in use before worrying about GPS. No receiver is immune, especially those not designed for military use.
Quote:
Originally Posted by midlifesailor
Lastly, I seriously doubt we are as prepared to deal with a localized jamming situation as our government would like us to believe.
I’m with you there. 24 hours is currently thought to be the minimum response time, and that’s under best conditions. The military may have the capability, but they won’t move until requested by the civilian authorities.
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