boscomantico wrote:
Huh? GPS approaches don’t use DME.The problem arises only with other (ILS, LOC, VOR, NDB) appraoches and these obviously don’t get “loaded”.
My point was that you can’t set up an approach manually in the GPS box because of the risk of making a mistake with a manual setup.
Trying to set up “a GPS equivalent to a DME” to me falls in the same category. I become convinced that manual setups are a bad idea after using a manual approach setup to coax a non-SBAS G1000 to provide an advisory glidepath for NPAs. It worked, but in no way would I try that for real in IMC. The risk of messing up is too great.
Gentlemen (und andere Leute),
Is this what we (Maule and Cirrus drivers) have been waiting for?
NCO.IDE.A.195 Navigation equipment
(a) Aeroplanes operated over routes that cannot be navigated by reference to visual landmarks shall be equipped with any navigation equipment necessary to enable them to proceed in accordance with:
(1) the ATS flight plan; if applicable; and
(2) the applicable airspace requirements.
(b) Aeroplanes shall have sufficient navigation equipment to ensure that, in the event of the failure of one item of equipment at any stage of the flight, the remaining equipment shall allow safe navigation in accordance with (a), or an appropriate contingency action, to be completed safely.
(c) Aeroplanes operated on flights in which it is intended to land in IMC shall be equipped with suitable equipment capable of providing guidance to a point from which a visual landing can be performed. This equipment shall be capable of providing such guidance for each aerodrome at t which it is intended to land in IMC and for any designated alternate aerodromes.
Paraphrasing, “if you can’t follow your flight plan by looking out of the window, you’d better have some other means of doing so”.
Is it really that simple? So where’s the trap?
I think en-route substitution was already no problem. So we’re talking about (c) above, that is approaches. There, I would argue that the phrase “suitable equipment” doesn’t leave any room to fly e.g. an approach which states “NDB and DME required” with only a GPS. At least I can’t see how you could argue that based on NCO.IDE.A.195 (c).
Or did I misunderstand your question?
Jacko wrote:
Paraphrasing, “if you can’t follow your flight plan by looking out of the window, you’d better have some other means of doing so”.Is it really that simple? So where’s the trap?
For IFR there is one trap. There is now also a part (d) of NCO.IDE.A.195:
(d) For PBN operations the aircraft shall meet the airworthiness certification requirements for the appropriate navigation specification.;
But of course that only applies in PBN airspace and/or on PBN routes.
Thanks, that is exactly the question, except that English courts tend to look at the meaning of whole phrases or sentences, rather than picking individual words – so that, for instance, an “antique firearm” is not just any firearm which is an antique.
On the one hand, “suitable equipment capable of providing guidance” does not mean “specified…” or “approved…” etc.
It could well be argued that a domestic long wave transistor radio is capable of providing guidance to or from an NDB without being, in the context of GA, altogether “suitable”.
It might be harder to draw that distinction in the case of a WAAS GPS receiver approved elsewhere for “use in lieu of ADF and/or DME”.
Incidentally, do some plates state “ADF and DME required”, or do they rather state “Procedure not available without NDB xxx and DME yyy”? If the latter, does it refer to the operational status of the nav aids or to the aircraft’s means of using them for guidance?
In US regulations, FAR 91.205(d)(2) states:
(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:
(1) Instruments and equipment specified in paragraph (b) of this section, and, for night flight, instruments and equipment specified in paragraph (c) of this section.
(2) Two-way radio communication and navigation equipment suitable for the route to be flown.
Although FAR’s don’t explicitly define the term equipment suitable for the route being flown, there is a definition of what constitutes a Suitable RNAV system in the definitions section of FAR 1.1.
Suitable RNAV system is an RNAV system that meets the required performance established for a type of operation, e.g. IFR; and is suitable for operation over the route to be flown in terms of any performance criteria (including accuracy) established by the air navigation service provider for certain routes (e.g. oceanic, ATS routes, and IAPs). An RNAV system’s suitability is dependent upon the availability of ground and/or satellite navigation aids that are needed to meet any route performance criteria that may be prescribed in route specifications to navigate the aircraft along the route to be flown. Information on suitable RNAV systems is published in FAA guidance material.
AC’s 90-100A (RNAV SIDS/STARS/OD), 90-101A (RNP-AR), 90-105A (RNP APR), 90-107 (LP and LPV), and 90-108 (Conventional Routes and procedures) define the suitability of RNAV equipment in various route/procedures in the US NAS. In general, an IFR GPS or GPS sensor that meets the requirements of TSO C129, C145/146, or C196 can be used to substitute for DME and ADF. Most of the first/second generation TSO C129 boxes can’t be used to substitute for VOR and are not approved for RNAV 1 procedures. For the GPS systems that are approved for VOR, they may substitute for VOR, ADF, and DME except for the final approach segment lateral guidance, which must use the actual VOR or ADF for primary lateral guidance. The GPS can substitute for any ATD or waypoint on the final approach course, just not for the lateral guidance unless “or GPS” appears in the procedure title. In the US, the approach procedures are a regulation and go thru the regulatory process. So if the procedure chart requires a specific piece of equipment and you are unable to use a GPS to substitute or it is needed to fly the lateral final approach course, you must have that equipment on board, the ground and aircraft equipment must be operating, or you are not equipped iaw 91.205 to fly that procedure, and you are not complying with the part 97 procedure.
The basic problem is that while the FAA has formalised these substitutions, and everybody knows where the FARs can be found (google 
) almost nothing like this has ever been published in Europe. And in the EU there is a lot of resistance to this.
Here, almost all assumptions about substitutions arise from “creative” reading of the wording of the regs.
One example is where a DME is called “distance measuring equipment”, where I would assume any lawyer with 2 braincells would get you off a prosecution, by showing that a GPS can measure distance. And I am evidently not the first person to have this view; some hundreds of SR22s have been flying in Europe “illegally” without ADF and DME, IFR, in airspaces which explicitly mandated DME and sometimes ADF for enroute IFR in CAS. Zero prosecutions… even in Germany which is the one place you would expect them if they happened anywhere at all.
I think the latest EASA regs provide even more opportunity for creative reading.
In the meantime I personally know a pilot in Switzerland (he doesn’t post here AFAIK) who had his initial JAA IR test, a few years ago, using GPS for VOR and NDB approaches, and the examiner wanted this, saying “that’s what you will do in reality!”.
But then Switzerland is non EU and was able to do various other things along those lines e.g. when trawling through national equipment carriage regs c. 2005 (for PPL/IR, when I was in there) I found a Swiss reg allowing an IFR GPS to eliminate the requirement to carry an ADF for IFR enroute! I can’t find that Swiss reference now, but it was here under Required Equipment where there is some other stuff.
Sorry for digging this thread out…I am actually trying to figure out at the moment if it is possible to fly SID/Enroute/STAR with a GPS only. The airplane I would use will have a GPS (like a GTN650) and two CDIs, however no DME/ADF etc.
I am pretty sure now that the en-route part would be no problem, while on approaches DME cannot be substituted (for sure not on the final approach, as I learned under the FARs).
I am not sure if I can fly SIDs and STARs without DME. Let’s say the ones at LSZG, they have waypoints with names which are in the GPS database. Therefore, I think, I could fly all procedures at LSZG with the exception of the VOR/DME approach. Any thoughts on this?
At least Autorouter gives me the SIDs and STARs in the suggested route, but I am not sure if this takes the equipment code (which I have entered) fully into account.
Thanks for the help to figure this out :)
Florian
If the procedure is in the IFR database and you load it as a procedure then you would use the GPS.
ArcticChiller wrote:
Sorry for digging this thread out…I am actually trying to figure out at the moment if it is possible to fly SID/Enroute/STAR with a GPS only.
Yes, published procedures should be in your database. GPS will navigate you perfectly well through them. Equipment carriage rules etc may be different but if you are asking about the capability of a GTN650, it will work.
