Suffix G

Ron Levy said:
No, it does not. See the AIM, 14 CFR 1.1, and the AC's on GPS's. There is no such thing in them as "VFR enroute/terminal" capability.
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The fact that something is not defined by the FAA does not mean that it doesn't exist, especially in the context of VFR navigation.

That is contrary to FAA guidance...
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In order for it to be contrary to FAA guidance, there would have to be some FAA guidance. Since the particular guidance we're talking about is using terms that are not defined in a VFR context, I'd say that what we're dealing with here is a lack of guidance.

...but nobody's going to care as long as you stay VFR -- including the controllers.
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Well at least we agree on that. And if I have to request an IFR clearance at some point during the flight, I won't be telling ATC that I'm /G if the plane I'm flying doesn't have an IFR-legal GPS installed.

When filling out a flight plan, I think it's important to look at what the information will be used for. Except for rare exceptions like DVFR, certain TFRs, departing class B airports, etc., the only thing a VFR flight plan will be used for is to help SAR people find you, so they should be filled out with that in mind. It makes no sense to limit VFR flight plans to IFR definitions of terms if there's ANY possibility that looser terminology may help you to be found. If the AIM says otherwise, then the AIM is wrong.

As for what the SAR folks will do with a VFR flight plan, I don't think they look anywhere beyond the route of flight block in order to choose a search area. Your route is their concern, not your navigational method.
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We look at anything that might give us a clue about the missing aircraft's whereabouts.
 
If you want SAR forget about a VFR flight plan. There is now only one way to initiate the SAR system from the beginning and that is to use a 406 device. You can buy a GPS equipped 406 PLB for <$200 now. There is no question about where you are, they know exactly within 15 minutes of activation.
 
Ron Levy said:
Depends on the vector. According to the FAA, you must be able to resume the cleared route after radio comm failure. As it says in 91.185(c)(1)(ii), "If being radar vectored, by the direct route from the point of radio failure to the fix, route, or airway specified in the vector clearance;" If you can't fly that direct route with your onboard gear, you can't accept the vector clearance.
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The problem with interpreting 91.185 as prohibiting you from accepting a vector that does not lead to something you are equipped to navigate to is that it would mean you couldn't accept vectors for a visual approach, you couldn't accept vectors for traffic, and you couldn't even accept a downwind leg vector for an approach you're equipped to fly, because it doesn't intersect the course that you're eventually going to intercept.

Remember, the AIM states explicitly that it's impossible to write a lost comm rule that would cover all situations. That argues strongly that the FAA does not want us to go overboard on taking 91.185 literally.

So, without a "suitable RNAV system," if they say, "Fly heading 140, join V123," it's no problem. If they say, "Fly heading 140, vectors to BONGO intersection," you must decline, although if BONGO is on V123, you can ask them instead for a vector to join V123.

That is in accordance with FAA guidance.
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Can you more specific? "FAA guidance" is like a needle in a hay stack.
 
Ron Levy said:
I highly doubt that. I'm sure they said something like "Fly heading 123, vectors for the ILS 9 approach." At least, that's what they're supoosed to do.
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I'm pretty sure that I've received vectors without hearing that, but even when they say it, how is that consistent with the alleged rule that a vector has to be to something you can navigate to? The first vector I get often does not intersect the approach course. And what about when they say "vectors for traffic," or "vectors for the visual approach"?
 
Henning said:
If you want SAR forget about a VFR flight plan. There is now only one way to initiate the SAR system from the beginning and that is to use a 406 device. You can buy a GPS equipped 406 PLB for <$200 now. There is no question about where you are, they know exactly within 15 minutes of activation.
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I don't think that even 406 devices activate 100% of the times that they're needed, but they are definitely a wise investment.
 
Palmpilot said:
The problem with interpreting 91.185 as prohibiting you from accepting a vector that does not lead to something you are equipped to navigate to is that it would mean you couldn't accept vectors for a visual approach, you couldn't accept vectors for traffic, and you couldn't even accept a downwind leg vector for an approach you're equipped to fly, because it doesn't intersect the course that you're eventually going to intercept.
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Not so. Vectors for a visual implies visual acquisition, and you are equipped for that. Vectors to final involves an approach you can fly on your own if you lose the vector. Vectors for traffic implies resumption of your original course, which we were equipped to fly.

Y'all have fun. I've pointed out the regs, and the FAA guidance is on record. I'm out.
 
Ron Levy said:
Not so. Vectors for a visual implies visual acquisition, and you are equipped for that. Vectors to final involves an approach you can fly on your own if you lose the vector. Vectors for traffic implies resumption of your original course, which we were equipped to fly.
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Yes, but in all those cases, unless you happen to be on the last one of the series of vectors that ATC often gives, there may not be a way to fly DIRECT to the course that you are equipped to navigate, and if there is, terrain may not allow it to be done safely. And with vectors for a visual, how are you going to navigate directly to the approach course if you haven't broken out yet when you lose comm?

The same considerations apply to a vector to an intersection or an airport, so I don't see how the alleged rule distinguishes between those and the cases where you say it's OK.

Y'all have fun. I've pointed out the regs, and the FAA guidance is on record. I'm out.
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No problem. As far as I know, participation in these discussions is voluntary. I just wish that SOMEONE could point out specifically where this guidance is.
 
olasek said:
That is correct, I only wonder how it was before when (unless I missed something) there were IFR-enroute certified receivers but not approach-certified. The equipment codes changed in 2005 but clearly there must have been a way to indicate such 'partial' capability.
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The first IFR GPS units had enroute, terminal, and approach capability. Only later were there IFR GPS units that had just enroute and terminal without approach capability introduced to the market. /G never indicated that the aircraft had approach capability, nor does it today. It also doesn't distinguish between WAAS capability with the ability to fly RNAV approaches to LPV, LP, or LNAV/VNAV minimums.
 
Palmpilot said:
...which presupposes that the pilot is conscious and able to get to the button.
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Generally of (s)he isn't, they're not gonna make it out alive anyway.

Those remote panel switches are a good idea though.

Conscious with injuries isn't gonna be a fun time to crawl over the back seat to get at the thing.
 
denverpilot said:
Generally of (s)he isn't, they're not gonna make it out alive anyway.

Those remote panel switches are a good idea though.

Conscious with injuries isn't gonna be a fun time to crawl over the back seat to get at the thing.
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Henning was talking about a personal locator beacon, but you still have to be able to press the button.
 
Palmpilot said:
...which presupposes that the pilot is conscious and able to get to the button.
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Well, if he's dumb enough to not keep it hanging on him or waits until after the crash to activate it, well, they're too stupid to live anyway. If they get completely blindsided by the accident, they aren't likely to have survived for a rescue. No, none of these devices survive 100+ G impacts, neither does your body. Arguments/excuses against buying a 406 device are totally ridiculous.
 
If you have an engine failure or are forced to ditch, hopefully you can activate the 406 ELT before you contact the ground. Otherwise, you depend on the G switch. Remember that it takes almost a minute after activation (manual or by the G switch) before the 406 ELT will send its first transmission.
 
John Collins said:
The first IFR GPS units had enroute, terminal, and approach capability. Only later were there IFR GPS units that had just enroute and terminal without approach capability introduced to the market.
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There were enroute/terminal GPS's on the market before the FAA even authorized GPS approaches -- in fact, I owned one (Trimble 2000T). At that time (1993-94, IIRC) the choice was to get e/t or wait for the approach GPS's to come out.
/G never indicated that the aircraft had approach capability, nor does it today. It also doesn't distinguish between WAAS capability with the ability to fly RNAV approaches to LPV, LP, or LNAV/VNAV minimums.
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Agreed.
 
Ron Levy said:
There were enroute/terminal GPS's on the market before the FAA even authorized GPS approaches -- in fact, I owned one (Trimble 2000T). At that time (1993-94, IIRC) the choice was to get e/t or wait for the approach GPS's to come out.
Agreed.
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He said 'The First', the Trimble 2000T was about 3rd or 4th gen aviation gear from Trimble. The first of the Trimbles I saw did indeed have vertical guidance and a worked a DGPS/LAAS system. I don't believe it was available to the public though.
 
Henning said:
He said 'The First', the Trimble 2000T was about 3rd or 4th gen aviation gear from Trimble. The first of the Trimbles I saw did indeed have vertical guidance and a worked a DGPS/LAAS system. I don't believe it was available to the public though.
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Well, if it wasn't available to the public, it wasn't "on the market." BTW, what year did you see that gadget?
 
Ron Levy said:
There were enroute/terminal GPS's on the market before the FAA even authorized GPS approaches -- in fact, I owned one (Trimble 2000T). At that time (1993-94, IIRC) the choice was to get e/t or wait for the approach GPS's to come out.
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Ron,

Good memory. The Trimble 2000T beat the Garmin GPS 155 TSO by two years, 1993 verses 1995. Thanks for the correction.
 
Ron Levy said:
Well, if it wasn't available to the public, it wasn't "on the market." BTW, what year did you see that gadget?
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Let's see, ran Westward summer 91, so corner of 91-92, likely early 92 because I had already started flying with Chooch and the gear was in his 421 for testing hardware systems and antennas.
 
Palmpilot said:
Henning was talking about a personal locator beacon, but you still have to be able to press the button.
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Ah. I skimmed too fast on the iPhone. Yeah. Didn't see PLB.

This got me thinking that nteresting problems arise for the DFers when you mix an ELT *and* a PLB. And no one (inland) trains on that scenario.

PLB will be slightly problematic if the ELT is also a 406 and they're both going off at the same time.

They'll double up on each other a little bit on 406, and make a total mess to DF on 121.5. Eventually both data bursts will get through on 406 on a doubled up 406 signal.

121.5 won't sound/work too great with a 121.5 only ELT plus a 406's weak 121.5 signal mixed either. Especially if you've done the cardinal "sin" in the backcountry and left the aircraft. The old 121.5 only ELT is a much stronger signal.
 
Henning said:
Well, if he's dumb enough to not keep it hanging on him or waits until after the crash to activate it, well, they're too stupid to live anyway. If they get completely blindsided by the accident, they aren't likely to have survived for a rescue. No, none of these devices survive 100+ G impacts, neither does your body. Arguments/excuses against buying a 406 device are totally ridiculous.
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I agree that buying a 406 device is a good idea. I'm just saying that there's no harm in providing additional information on a VFR flight plan, even if the information doesn't comply with IFR definitions of terms, and it could conceivably help. If the pilot puts "direct" in the route box, then one of the things SAR people are going to do is draw a straight line from the departure point to the destination and see what high terrain it intersects. If the pilot has a GPS on board, that increases the likelihood of the wreck being along that line. If not, then the deviations from a direct route are likely to be larger. The pilot may have written "direct" because of not knowing how to precisely describe the intended route, not bothering to do so, or not having more than a general idea of what route he/she is going to fly.
 
denverpilot said:
Ah. I skimmed too fast on the iPhone. Yeah. Didn't see PLB.

This got me thinking that nteresting problems arise for the DFers when you mix an ELT *and* a PLB. And no one (inland) trains on that scenario.

PLB will be slightly problematic if the ELT is also a 406 and they're both going off at the same time.

They'll double up on each other a little bit on 406, and make a total mess to DF on 121.5. Eventually both data bursts will get through on 406 on a doubled up 406 signal.

121.5 won't sound/work too great with a 121.5 only ELT plus a 406's weak 121.5 signal mixed either. Especially if you've done the cardinal "sin" in the backcountry and left the aircraft. The old 121.5 only ELT is a much stronger signal.
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The 406 ELT/PLB technology will not interfere with one another, at least not for long. The digital burst is short (under a half a second) and high power. So the transmission duty cycle is less than 1%. To keep two 406 devices from stepping one each other, they only transmit nominally every 50 seconds +/- 2.5 seconds. There is a designed in randomizing function that changes the next transmission to be 50 seconds +/- a random time within the 5 second window. So even if they occasionally step on each other for a part of a transmission, the odds are very high that they won't step on each other during the next transmission. The digital 406 MHz signal is not suitable for homing because it isn't continuous and only transmits approximately 1% of the time.
 
Right. They interfere but not for long.

It still can be significant to the math if the satellite is only hearing, say, 10% of transmissions due to the ELT being buried in a crumpled tail under a wet canopy of trees.
 
Oh and burst homing is possible.

You just need gear that understands that it's looking for bursts and only gives DF steer information for the bursts, not continuously. Even better if it will automatically plot bearing to target on a moving map as the DF station moves.

Simple systens even are usually accompanied by a "count" or "timer" displayed to the DF user of "time since last signal", so the operator knows if they got shadowed or moved out of range.

Many Doppler based DF units have such a mode. Especially if they integrate with a PC.

The DF gear aboard CAP aircraft also has such a mode but it's not nearly as accurate as the Doppler gear I've used or gotten to play with. It points and pauses, showing a count-down. Once in close, the crew can switch to the 121.5 sweep which is nearly continuous.

FCC has the best stuff. Their vans are downright awesome. Hidden antenna arrays along the roofline, killer Doppler-based wide-spectrum DF capable of pinpointing very short duration non-repetitive transmissions.

I WANT their toys. :)

I'm not going to be able to afford those any time soon. Nor would I say it's on even the top-third of my fiscal priorities list.

Fun to own if you had a business case for it, though. All it takes is some relative motion and about three transmissions and they'll be within a block of the source. For low-band/HF stuff, their fixed monitoring stations do it in near-real-time.
 
denverpilot said:
Oh and burst homing is possible.

You just need gear that understands that it's looking for bursts and only gives DF steer information for the bursts, not continuously. Even better if it will automatically plot bearing to target on a moving map as the DF station moves.

Simple systens even are usually accompanied by a "count" or "timer" displayed to the DF user of "time since last signal", so the operator knows if they got shadowed or moved out of range.

Many Doppler based DF units have such a mode. Especially if they integrate with a PC.

The DF gear aboard CAP aircraft also has such a mode but it's not nearly as accurate as the Doppler gear I've used or gotten to play with. It points and pauses, showing a count-down. Once in close, the crew can switch to the 121.5 sweep which is nearly continuous.

FCC has the best stuff. Their vans are downright awesome. Hidden antenna arrays along the roofline, killer Doppler-based wide-spectrum DF capable of pinpointing very short duration non-repetitive transmissions.

I WANT their toys. :)

I'm not going to be able to afford those any time soon. Nor would I say it's on even the top-third of my fiscal priorities list.

Fun to own if you had a business case for it, though. All it takes is some relative motion and about three transmissions and they'll be within a block of the source. For low-band/HF stuff, their fixed monitoring stations do it in near-real-time.
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Nate brings up a very interesting scenerio... The 406 does broadcast in 'bursts' so tracking them is problematic.. The Mooney that crashed in the Wind River range last fall with the father and three kids from Minn was a really bizarre search.. It had only a 121.5 ELT and for some as yet unknown reason it only broadcasted in 6 second bursts,,,, then it stayed quiet for 20 minutes or so and let out another 6 second burst.. It took the CAP a while to home in on it but they did an outstanding job considering the challenges they faced... It is presumed the ELT had some kind of power supply failure or maybe a occilator that heated up and opened its circuit and when it cooled down it would work for a few seconds till it heated back up again, only to quit broadcasting for another 20 minutes or so... Strange deal indeed..:yesnod:
 
dell30rb said:
I file /U and get cleared direct to my destination all the time. I don't ask for it either. Once I was in the process of flying my filed route to a VOR and the controller said I was cleared direct, and then asked if I needed to go to the VOR for navigational reasons. I stayed on course because the direct route would have taken me into a mean looking cloud

I am new so this may be incorrect, but it seems like ATC will assume you have a VFR GPS and clear you direct to your destination if you are within radar coverage
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I've never heard a /U getting cleared direct to an airport around here, but they'll frequently clear you direct to an out of range VOR via a heading.
 
The ELT side-discussion is giving me evil ideas for a modification to a practice beacon. ;)
 
The controllers have your suffix right there in front of them so they know you are a /U. Most planes they work, however, are /G, /R, /L, or /Q with the occasional Delta being /W and some GAs being /A, so they tend to forget if they arent looking at your strip when they issue it.
Bring the GPS, file a /U appropriate flight plan and ask for shortcuts to intersections. On the other hand, if you truly are a /U or /A and they clear you direct, ask for vectors to the intersection. If they are busy, they will tell you to remain on course, if not they will give you those vectors.
 
milkman dan said:
The controllers have your suffix right there in front of them so they know you are a /U. Most planes they work, however, are /G, /R, /L, or /Q with the occasional Delta being /W and some GAs being /A.
Bring the GPS, file a /U appropriate flight plan and ask for shortcuts to intersections. On the other hand, if you truly are a /U or /A and they clear you direct, ask for vectors to the intersection. If they are busy, they will tell you to remain on course, if not they will give you those vectors.
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They still have the DC-9-50's?
 
Henning said:
I can't recall seeing one outside Indonesia/SE Asia & Africa markets in years, but I don't fly Delta.
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ATL-PHL sees about 1 a day. I have heard that they are pulling some out of mothballs to cover routes that dont sell enough to use a MD80.
 
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milkman dan said:
On the other hand, if you truly are a /U or /A and they clear you direct, ask for vectors to the intersection. If they are busy, they will tell you to remain on course, if not they will give you those vectors.
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Some people think that 91.185 makes it illegal to accept such a vector.

I have also heard that there is FAA guidance that you can't accept such a vector, but no one seems to be willing to say where that guidance may be found. (Apparently it's a secret.)
 
Palmpilot said:
A non IFR-certified GPS may not have en route and terminal capability for IFR purposes, but it does have those capabilities for VFR purposes.

I file VFR flight plans /G based on a non IFR-certified GPS because if search and rescue personnel have to come looking for me, I want them to know what VFR navigation equipment I have.
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And what decision do you think they are going to make based on your equipment suffix. The answer is none. They're going to look at everywhere you could have flown given the fuel on board that you listed. If your VFR even with NO RADIOS AT ALL you could fly any route. Have you heard of pilotage, dead recconing?
 
Palmpilot said:
Some people think that 91.185 makes it illegal to accept such a vector.

I have also heard that there is FAA guidance that you can't accept such a vector, but no one seems to be willing to say where that guidance may be found. (Apparently it's a secret.)
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Nobody's going to report you for a PD if they give you a direct clearance and you take it. Just make sure you actually go direct and not a 20nm wide arc between the 2 points.
 
flyingron said:
And what decision do you think they are going to make based on your equipment suffix. The answer is none. They're going to look at everywhere you could have flown given the fuel on board that you listed. If your VFR even with NO RADIOS AT ALL you could fly any route. Have you heard of pilotage, dead recconing?
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The FAA does not consider pilotage and DR as suitable means per 91.205(d)(2) for navigating under IFR except as published for limited segments of some SIAP's. VFR, they don't care as long as you don't violate any airspace.

As for vectors under IFR, you can always take a vector, but eventually you have to navigate somewhere, and that somewhere has to be something for which you have the suitable equipment on board.
 
milkman dan said:
Nobody's going to report you for a PD if they give you a direct clearance and you take it. Just make sure you actually go direct and not a 20nm wide arc between the 2 points.
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As long as nothing goes wrong, you're probably right, but don't do it on an IR practical test. However, if you do cause a problem because you accepted a clearance for which you didn't have the suitable equipment on board (see 14 CFR 1.1 for the definition of that), you can get hammered -- see Administrator v. Fausak.
 
Ron Levy said:
The FAA does not consider pilotage and DR as suitable means per 91.205(d)(2) for navigating under IFR except as published for limited segments of some SIAP's. VFR, they don't care as long as you don't violate any airspace.
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For completeness, DR is used under IFR for any heading used in a procedure such as on a DP, ODP, SID, Hold, PT, and on airways with MEA gaps. There may be others, but these are the ones I could think of off the top of my head.
 
John Collins said:
For completeness, DR is used under IFR for any heading used in a procedure such as on a DP, ODP, SID, Hold, PT, and on airways with MEA gaps. There may be others, but these are the ones I could think of off the top of my head.
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Thanks for expanding that. But in each case, the use of DR is specified or required as part of the procedure. Using DR for enroute IFR navigation (other than a celestial navigation route, in which case a rated Flight Navigator becomes part of your required equipment) to go direct is not approved.
 
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