Say im landing somewhere with an RNAV approach it basically seems identical to an ILS approach only I don’t have to input an ILS frequency and can’t use approach mode when autopilot is activated… are these the only differences ? RNAV seems just as accurate as ILS so is the only advantage to using ILS that the you can use approach mode ?
Just trying to see what differentiates an RNAV approach to an ILS approach.
There are many airports in the US that do not have localizers and can only be landed in IMC using RNAV approaches.
It works with both 
Airports are trying to move aircraft to RNAV from ILS. The advantage is that RNAV doesnt depend on anything on the ground and is therefore much less expensive for airports. As GPS becomes more and more reliable and accurate, it gets better for navigating aircraft onto the runway. Also they dont have to maintain and recalibrate ground euipment all the time to avoid crashing aircraft into the ground. IF Air safety and airport people had their way, all aircraft would have RNAV capability and airports could do away with ILS euipment altogether. That’s the real world situation, so you’ll see more and more emphasis on RNAV as time goes along.
Cheers
Mike Kear
Windsor, NSW, Australia
RNAV is heavily limited by aircraft capability, companyapprovals and training all of which cost plenty.
ILS isnt going anywhere just yet as what was seen by the Gold Coast forced to install one to actually get the Chinese carriers to fly in.
LNAV/VNAV still doesnt have ILS minimas at many airports as some with obstacle free approach paths it does so its great for some airports.
Low vis procedures likewise use ILS with GLS not having minimums needed for low vis.
Its coming, the rules change daily, procedures are changing contimually it really is a large part of the future.
But its a fair way off replacing ILS yet…