Originally Posted by Islander2
Since you had stated, unequivocally, that the use of GPS is NOT LEGAL as a primary means of navigation in UK airspace, I was hoping (as, I know, were others) that you could put this debate to rest by quoting law (ie ANO or Eurostuff) rather than operational guidelines.
But leaving the legalities to one side, let's consider the logic. GPS is approved, or shortly to become approved, as the primary navigation means for:
1. IFR in BRNAV controlled airspace, with direct clearances that can be greatly in excess of 100nm;
2. IFR in PRNAV exceptionally-busy TMA airspace, flying SID's and STAR's to very tight track-error tolerances; and
3. IFR non-precision approaches in IMC to NDB minima or lower.
But it's not suitable as the primary navigation means in VFR in the open FIR? Laughable ... and a quite unsustainable position, since most pilots know first hand that with the right equipment, knowledge and SOP's it is at least as good a navigation method as anything else that is available.
Er. No 3. Where is your information for this? 1 & 2 are already accepted. 3 isnt and I havent seen a proposal in the UK for this - I would be interested in reading the background material - out of curiosity - and I would add that all approaches to a/d under IMC must be published approaches.
GPS is no worse than anything else? I believe that the reservations regarding GPS come down to the amount of electronics required to block GPS and cause serious disruption to air traffic - as I understand it the low level of the GPS signal means that relatively small transmitters and cheap electronics could block GPS signifcantly - however, to do the same to an ILS or VOR etc requires significantly higher power transmitters...but thats all hearsay but i thought id mention anyway.