Define RNAV

[Walker]

Quick question; im going through some paperwork, whats the actual acronym for RNAV actually stand for? Area Navigation? or is there more to the story?
I'm asking because im studding up for my samra/saron and the books im going through are calling it "random area navigation" and this same series of books is calling RAIM "Random Autonomous Integrity Monitoring" which is total BS, so im inclined to think this "random area navigation" thing is also BS....
ideas?

[Pygmie]

I don't know where the random came from.

RNAV = Area navigation

http://www.tc.gc.ca/CivilAviation/publi ... -0.htm#5-2

[xsbank]

RAIM Receiver autonomous integrity monitoring - a prediction of whether there will be sufficient satellites available at the time of your approach to meet the accuracy requirements. RNAV may or may not be GPS-based, yet RAIM is a measure specific to GPS.

[Carrier]

RNAV used to be the term for area navigation, as in cross-country navigation. Now it seems to be used for instrument approaches, a phase of flight that should require considerably tighter flying standards and precision than basic cross-country navigation. Is a GPS approach now "Area navigation" and is it satisfactory and safe to fly a GPS approach to cross-country navigation standards? If so, look out for a few more CFITs!

[Spokes]

RAIM Receiver autonomous integrity monitoring - a prediction of whether there will be sufficient satellites available at the time of your approach to meet the accuracy requirements. RNAV may or may not be GPS-based, yet RAIM is a measure specific to GPS.

In addition to making sure there are enough satellites available, RAIM also makes sure that thier distribution in the sky is wide enough to provide the accuracy required. If there were 5 satelittes available, but the were all crowded in a small spot of the sky, the accuracy needed might not be there.

[Pratt X 3]

More info on RNAV found in the COM section of the AIM. Breezes over the less used/older systems then goes into detail on GPS(GNSS).

http://www.tc.gc.ca/CivilAviation/publi ... 0.htm#3-15

RNAV used to be the term for area navigation, as in cross-country navigation. Now it seems to be used for instrument approaches, a phase of flight that should require considerably tighter flying standards and precision than basic cross-country navigation. Is a GPS approach now "Area navigation" and is it satisfactory and safe to fly a GPS approach to cross-country navigation standards? If so, look out for a few more CFITs!

GPS approaches are flown to a narrower standard than en-route or cross-country navigation. The latest standards for RNAV are called RNP (Required Navigation Performance). Avionics are certified to the RNP value that will determine the use based on a tolerance of maintaining the aircrafts position. They are:

RNP 2.0 - Terminal and Enroute Operations
RNP 1.0 - Terminal Operations
RNP 0.3 - Approach Operations

RNP 0.3 represents a distance of 0.3 nautical miles either side of the centerline. RNP 1.0 and 2.0 are 1 NM and 2 NM either side of the centerline. You might come across RNP-1 or RNP-5 which are European RNAV standards as well as RNP-4 and RNP-10 which are Oceanic RNAV standards.

For more info, check out:
http://www.tc.gc.ca/CivilAviation/publi ... 0.htm#3-16

[Vandriver]

My understanding of RNAV (Area Navigation) is that the term originated from the old onboard computer systems that plotted relative bearing and distance from VOR stations, allowing navigation to or from any point within coverage of the VOR/DME system. ie. not specifically to the VOR. The interface allowed the user to navigate using lat/long coordinates. The more modern use of the term is any system that will allow point-to-point navigation. (again, not to VOR's but to any waypoint defined by the user or stored in a database) These systems include GPS, INS, LORAN, etc. and of course the original VOR/DME based RNAV as described above.

[Doc]

Way back when pterodactyls really needed to know where the old cave was, RNAV was a ground based system with which you could "create" a VOR by displacing it along a specific radial. You would loose it down low if you were too low to receive info from the originating VOR. I knew a guy who could shoot a "VOR" approach to his cottage using RNAV. It has/had no relationship whatsoever with the GPS based RNAV we use today.

[Cat Driver]

Doc, I had RNAV in my Geronimo in my flight school in 1988 and could move the Vancouver VOR to the end of runway 16 in Nanaimo and use it as a pseudo ILS localizer...worked like a charm.

I didn't put one in my R22 though.

[Benwa]

Here is what I heard from different instructors:

RNAV =

Area Navigation
Random Navigation
Range Navigation (that one i heard maaaaaaany times)
Receiver Navigation
oh and Radio-Navigation...

So have at 'er !


I'll stick to Area Nav though.

[Stick Shaker]

Benwa,

You really heard this crap from "qualified" flight instructors ??!!

Maybe their chief instructor should be made aware of this...

[Benwa]

I heard a lot of crap coming from instructors through the years... Maybe we could all write a book we could then give to the Chief instructors ?

[scopiton]

but does the CFI know something about Rnav... ummm ?

[Cat Driver]

Here is a question for you flight instructors, what are your opinions on the difference between INS and RNS?

[switchflicker]

Same as the difference between your age and mine!!!

Switch

[Cat Driver]

Well switchflicker I have no idea what that difference would be but what I am interested in is how you found the two systems to be for say accuracy and user friendliness.

[bbb]

Cat, you should ask them to define RR nav.
Remember when LORAN was going to be the be-all and end-all to navigation?
Now, even our piston twins have dual WAAS equipped RNAV, with user interfaces that don't require an engineering degree to operate!
(although, I don't think nearly enough pilots, including myself, get deep enough into them to know what ALL the shortfalls are under all possible circumstances-- still insist on backing it up with old technology whenever its available)

[Cat Driver]

Technology just leaps ahead so fast one can hardly keep up with it.

Remember GNS 100?

I first used that in a Twin Otter in 1975 and thought things couldn't get better.....ha ha ...I fuckin near killed myself one night because I got to complacent and decided I wouldn't wait twenty minutes to warm the thing up and program it for a return trip.

INS like the GNS has been replaced by RNS...at least that was where I left the game a few years ago.

Right now I'm beavering away to see if I can get a successful transplant of a brain...I want to transplant a Newfoundland dogs brain in a woman so I would have the ideal companion.

[Four1oh]

the slobber would get to me after a while...

[Cat Driver]

Not all Newfoundland dogs slobber. I will choose the brain carefully.