Flying IFR in a VFR only plane and iPad

BobThePilot

BobThePilot

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There have been times when I've been in a VFR only plane and wondered if someone in a similar situation could file IFR and basically just use their iPad to navigate (announcing themselves as a /G). Is there any way ATC would know? For example if they called them up and used a tail number for a plane they know is /G is there any way ATC would know? Is there any hidden code in the transponder that identifies the real plane that you are flying?

Please no lectures on how the iPad GPS is not reliable, etc, I know that, just want to understand how ATC would be able to prevent something like this.
 
Depends on the type of transponder in the aircraft.
 
BobThePilot said:
There have been times when I've been in a VFR only plane and wondered if someone in a similar situation could file IFR and basically just use their iPad to navigate (announcing themselves as a /G). Is there any way ATC would know? For example if they called them up and used a tail number for a plane they know is /G is there any way ATC would know? Is there any hidden code in the transponder that identifies the real plane that you are flying?

Please no lectures on how the iPad GPS is not reliable, etc, I know that, just want to understand how ATC would be able to prevent something like this.
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It's not ATC's job to prevent something like that. So long as there is no deviation ATC probably doesn't give a hoot and probably doesn't even know. Many of us have received direct clearances IFR without filing /G.
 
ATC has no way of knowing what you've really got in the airplane other than by how you fly. As long as you're able to be exactly where they tell you to be, they won't notice or care. However, if anything happens to induce them to complain to the FSDO, or anything else causes you to come to Flight Standards' attention, those folks will have no trouble at all determining what equipment you actually had installed. Once that happens, you are facing enforcement action for what I'm sure they will call violations of both 91.205 and 91.13. That's a 30-90 day suspension by FAA Order 2150.3B (Table B-3-h, item 16), and given the willful nature, I'd expect the max.

See Administrator v. Fausak for an example of someone who asked for and tried to fly a VOR/DME approach without a DME, and whose aimless wandering caused ATC to file a Pilot Deviation report. Note that he got a 180-day suspension for violating 91.13(a) and 91.205(a) and (d)(2).
 
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Nope, if you're on the route and altitude they want, nobody will be the wiser.

I know a guy who has a /U BE55 with only one VOR receiver; He, for some reason, always files as /G. :confused: (He wanted me to do a few IFR trips with him to help with proficiency. After learning about the aforementioned and hearing the comments from his mechanic, I declined...)
 
Heck, ATC doesn't know if you even have a pilot's certificate. Sheesh :/

Listen, if you're IFR rated, current, and equipped you can always do the poor man's /G (while truthfully filing your equipment type) using your ipad/vfr GPS/eyeballs and ask for a heading (or even suggest one), and "direct when able" to some fix you can legally navigate to. Now you're legit.
 
If you air file - sometimes ATC will ask you if you are IFR equipped and legal . . . answer in the affirmative and it not be the truth then you are subject to an 18USC1001 prosecution . . .

Its not ATCs job to prevent you from breaking the law.
 
i flew IFR in a cherokee that had a VFR gps. sure i could have filed /G and ATC probably wouldn't have known. i filed /U and did the right thing. they gave me a direct clearance and i told them i was unable to and i was /U even though i could have flown direct the VFR GPS. bottom line is do the right thing and follow the rules
 
jordane93 said:
i flew IFR in a cherokee that had a VFR gps. sure i could have filed /G and ATC probably wouldn't have known. i filed /U and did the right thing. they gave me a direct clearance and i told them i was unable to and i was /U even though i could have flown direct the VFR GPS. bottom line is do the right thing and follow the rules
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Just tell them you're "vector qualified" and you recommend a heading of about... (Read GPS screen)... Until receiving XXX then direct XXX. ;)

In good weather, anyway...
 
Same question as for any other hand held GPS. Of course, it depends what you mean by VFR plane. With the exception of GPS, there's not a whole lot of "IFR" certification for NAV units other than the 30 day VOR self-test.

The scarier thing would be not knowing how well your static system is really working.
 
flyingron said:
Same question as for any other hand held GPS. Of course, it depends what you mean by VFR plane. With the exception of GPS, there's not a whole lot of "IFR" certification for NAV units other than the 30 day VOR self-test.



The scarier thing would be not knowing how well your static system is really working.
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So being an engineer and literally minded, I have to ask...

Are you seriously saying if the static tests are done it's a good idea?

I say no. It's more about the human and their proven ability than the gear. But I think you'll agree.


If you agree, why even bring up the static test? They don't fail all that often and the majority of failures are easily seen by a VFR pilot on all those days they're not breaking any rules.

Any altitude error is rarely big enough to cause a loss of separation except in RVSM airspace. And airspeed errors are definitely not going to be missed by a pilot even halfway clueful.
 
The OP's question reminds me of folks I know who brag about their techniques for getting out of jury duty, as if you have to be especially clever to manage it.

It doesn't take any particular smarts to get out of jury duty. Similarly, you don't have to be a genius to break any number of flight regs without anyone knowing.

As someone mentioned earlier, ATC doesn't know if you've got a pilot's certificate. Or a medical. Or if your currency requirements are met. Or if your plane is airworthy. Or, or, or...

In other words, it's easy to be dumb and do the wrong thing.
 
You can do whatever you want. But....if there's a problem, if there's an incident, if there's a crash, if there's any type of investigation.....you are toast. Neither the airplane insurance nor your life insurance nor your medical insurance will pay anything. If you have a family, they're screwed because they will be sued for everything. If you managed to live, you will be screwed because the FAA will ground you for life, the lawyers will have a field day.

Do you feel lucky? Do you trust the iPad with your life and bank account?
 
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denverpilot said:
If you agree, why even bring up the static test? They don't fail all that often and the majority of failures are easily seen by a VFR pilot on all those days they're not breaking any rules.
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What's scary is that you can legally fly an approach to minimums with an altimeter that reads + or - 75 feet.
 
Jim_R said:
The OP's question reminds me of folks I know who brag about their techniques for getting out of jury duty, as if you have to be especially clever to manage it.
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Where was I bragging? And I welcome Jury duty. It's an opportunity to get off work for a day or so! Problem is I'm always disqualified. I don't know why. I really try hard to make the cut though.

Jim_R said:
It doesn't take any particular smarts to get out of jury duty. Similarly, you don't have to be a genius to break any number of flight regs without anyone knowing.
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Really? I would never have known that! So if you put someone with the mental capacity of a two year old at the controls and they break a flight reg this does not mean they are a genius? Astounding! Thank you for this pearl of wisdom! ;)

Jim_R said:
In other words, it's easy to be dumb and do the wrong thing.
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Well, sir, you're the dumb**** here for not reading my post correctly and doing the wrong thing by posting some rubbish response to questions I did not pose.

:nono:
 
In a similar vein to the OP...

...I was wondering if there was any way ATC can tell if I'm high on glue when I'm flying?

Then again, how can I tell if they are?

airplane%20lloyd%20bridges%20high.JPG
 
murphey said:
You can do whatever you want. But....if there's a problem, if there's an incident, if there's a crash, if there's any type of investigation.....you are toast. Neither the airplane insurance nor your life insurance nor your medical insurance will pay anything. If you have a family, they're screwed because they will be sued for everything. If you managed to live, you will be screwed because the FAA will ground you for life, the lawyers will have a field day.

Do you feel lucky? Do you trust the iPad with your life and bank account?
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agreed. It's like flying without a PPL or driving with a suspended DL. No one knows or cares until somethings happens. Then you're F'ed.
 
comanchepilot said:
If you air file - sometimes ATC will ask you if you are IFR equipped and legal . . . answer in the affirmative and it not be the truth then you are subject to an 18USC1001 prosecution . . .
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That's true in theory, but in reality, the FAA normally settles for just an emergency revocation when you deliberately lie to them like that.

Its not ATCs job to prevent you from breaking the law.
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That's really nobody's job but your own. The FAA doesn't get involved in that other than to let you know what the law is and then punish you if you break it. Prevention is the job of your conscience, not the FAA. :wink2:
 
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denverpilot said:
Any altitude error is rarely big enough to cause a loss of separation except in RVSM airspace.
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Given that you may have as little as 75 feet of obstruction clearance at the bottom of an ILS approach, I'd say knowing that your altitude measuring system is working to FAA specs is pretty important to IFR operations.
And airspeed errors are definitely not going to be missed by a pilot even halfway clueful.
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The only part of your airspeed system which is tested during the 91.411 tests is the static side of your airspeed indicator, and that only for leakage. There is nothing checked on the pitot system or the ram pressure side of the altimeter.
 
dell30rb said:
What's scary is that you can legally fly an approach to minimums with an altimeter that reads + or - 75 feet.
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That's one reason the obstruction clearances on IAP's are what they are -- usually 250-300 feet on non-precision approaches, and 75 feet at the bottom of an ILS with 200 DH. Note that there are other factors which can have you lower than you think you are even with a perfect altimeter-static system, including temperature and wind. See this accident report for more on that.
 
BobThePilot said:
Where was I bragging? And I welcome Jury duty. It's an opportunity to get off work for a day or so! Problem is I'm always disqualified. I don't know why. I really try hard to make the cut though.


Really? I would never have known that! So if you put someone with the mental capacity of a two year old at the controls and they break a flight reg this does not mean they are a genius? Astounding! Thank you for this pearl of wisdom! ;)



Well, sir, you're the dumb**** here for not reading my post correctly and doing the wrong thing by posting some rubbish response to questions I did not pose.

:nono:
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I think you may have read something into his response. Jim didn't mention you, he referred to your post. What you ask in the post would be dumb to do, but no one said that was you.

Jim's a good guy. Let's keep this civil.
 
dell30rb said:
What's scary is that you can legally fly an approach to minimums with an altimeter that reads + or - 75 feet.
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Ron Levy said:
Given that you may have as little as 75 feet of obstruction clearance at the bottom of an ILS approach, I'd say knowing that your altitude measuring system is working to FAA specs is pretty important to IFR operations.
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Being within specs is important, but on an ILS you should be following the glide slope. If the altimeter reads 75' too high, you'll descend below minimums that much before indicating DA, reducing the obstacle clearance. It doesn't mean you won't have any clearance at all, just less of it. How much less? If the obstacle clearance surface (OCS) is a 34:1 slope, the OCS is 88' at 1/2 mile, resulting in a normal clearance of 112' for a 200' DH. So if you drop another 75' on a 3° glide slope (20:1) you'll move about 1/8 mile [EDIT catch by ronachamp: "about 1/4 mile"] closer to the runway--about 1500'. The OCS gets lower, too, about 44' lower (1500 / 34) for a net clearance of 68', or almost twice the allowable altimeter error.

Ron Levy said:
That's one reason the obstruction clearances on IAP's are what they are -- usually 250-300 feet on non-precision approaches, and 75 feet at the bottom of an ILS with 200 DH.
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I get 112' of obstacle clearance at DH. See above.

dtuuri
 
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dtuuri said:
Being within specs is important, but on an ILS you should be following the glide slope. If the altimeter reads 75' too high, you'll descend below minimums that much before indicating DA, reducing the obstacle clearance. It doesn't mean you won't have any clearance at all, just less of it. How much less? If the obstacle clearance surface (OCS) is a 34:1 slope, the OCS is 88' at 1/2 mile, resulting in a normal clearance of 112' for a 200' DH. So if you drop another 75' on a 3° glide slope (20:1) you'll move about 1/8 mile closer to the runway--about 1500'. The OCS gets lower, too, about 44' lower (1500 / 34) for a net clearance of 68', or almost twice the allowable altimeter error.


I get 112' of obstacle clearance at DH. See above.

dtuuri
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maybe you do, maybe you don't...

http://www.ainonline.com/aviation-n...ws/2012-08-01/fly-plate-and-you-wont-get-hurt
 
Ron Levy said:
Given that you may have as little as 75 feet of obstruction clearance at the bottom of an ILS approach, I'd say knowing that your altitude measuring system is working to FAA specs is pretty important to IFR operations.
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In what way?
 
dtuuri said:
Being within specs is important, but on an ILS you should be following the glide slope. If the altimeter reads 75' too high, you'll descend below minimums that much before indicating DA, reducing the obstacle clearance. It doesn't mean you won't have any clearance at all, just less of it. How much less? If the obstacle clearance surface (OCS) is a 34:1 slope, the OCS is 88' at 1/2 mile, resulting in a normal clearance of 112' for a 200' DH. So if you drop another 75' on a 3° glide slope (20:1) you'll move about 1/8 mile closer to the runway--about 1500'. The OCS gets lower, too, about 44' lower (1500 / 34) for a net clearance of 68', or almost twice the allowable altimeter error.
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75' on a 3° glide slope will move about 1/4 mile closer to the runway.
 
roncachamp said:
75' on a 3° glide slope will move about 1/4 mile closer to the runway.
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I'm surprised if that's the only mistake I made at two o'clock in the morning, but whoever can find another will benefit from the treasure hunt more than I will. Good catch, will fix.

Adding another wrinkle, if we all agree the situation isn't as dire as Cap'n Ron makes it when the altimeter is off by 75', what is the minimum potential obstacle clearance if you aren't actually on the glide slope, i.e., you're bracketing it within limits and below it at DA? (Must show work and references for the other students)

dtuuri
 
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I would have no qualms filing as a /U and using my Ipad as a secondary backup.
 
There were no correct answers to the question:
dtuuri said:
Adding another wrinkle, if we all agree the situation isn't as dire as Cap'n Ron makes it when the altimeter is off by 75', what is the minimum potential obstacle clearance if you aren't actually on the glide slope, i.e., you're bracketing it within limits and below it at DA? (Must show work and references for the other students)
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AIM figure 1-1-7 indicates the width of the glide slope scale to be + or - .7°.

Assuming 3/4 scale deflection (max allowable in PTS), gives .525° below glide slope.

At one mile (6000' nominal), that's 52.5'.

At 3000' (1/2 nm), that's 26'.

At 1500' (1/4 nm), that's 13'.

So, since you have 68' of normal obstacle clearance if you descend 75' below true DA because of your max allowable altimeter error (see this post), you now have only 55' of clearance (68' - 13')--even if you fly the approach to the least acceptable PTS limit.

dtuuri
 
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BobThePilot said:
Is there any hidden code in the transponder that identifies the real plane that you are flying?
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Search for a random (accurate) tail number through your favorite online search engine... for example, N671MA, and open one of the several registration information pages you'll find... look for a "mode S code" (easily found on https://flightaware.com/resources/registration/N671MA). That gets put out by your mode S transponder (if so equipped). I hadn't noticed this previously, but lower on that page is a history of known mode S codes for this aircraft (which, for this example, has no changes).

If you just search for screenshots of traffic monitoring systems, you'll find some that include the tail numbers -- even when the system is just an iPad coupled to a $1000 piece of portable hardware.
 
When instrument procedures and routes are developed, do people think the terpsters ignore equipment errors?
 
comanchepilot said:
If you air file - sometimes ATC will ask you if you are IFR equipped and legal . . . answer in the affirmative and it not be the truth then you are subject to an 18USC1001 prosecution . . .

Its not ATCs job to prevent you from breaking the law.
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It's also not their job to protect you from your own stupidity.

As long as you can fly within tolerance, you can get away with anything. If you end up with a pilot deviation though, you will have to answer for that minimally with a 44709 ride. If you lose control, well, you may answer to a higher authority.
 
Henning said:
As long as you can fly within tolerance, you can get away with anything. If you end up with a pilot deviation though, you will have to answer for that minimally with a 44709 ride.
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709 rides are used to handle matters of pilot competency, not deliberate violations of the regulations, which are normally handled with enforcement actions (administrative actions being generally reserved for mistakes, not deliberate violations).
 
Ron Levy said:
709 rides are used to handle matters of pilot competency, not deliberate violations of the regulations, which are normally handled with enforcement actions (administrative actions being generally reserved for mistakes, not deliberate violations).
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I said minimally, and I guarantee a 709 ride will be involved along with whatever else. If a decision like that isn't indicative of a problem with pilot competence, I'm not sure what is.
 
Henning said:
I said minimally, and I guarantee a 709 ride will be involved along with whatever else. If a decision like that isn't indicative of a problem with pilot competence, I'm not sure what is.
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I think your idea of the meaning of the word "competency" and the FAA's idea on that diverge significantly.
 
Ron Levy said:
Error bounds are built into the obstruction clearance limits they use.
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yeah I know. That was point of the question...to try to get some folks to think it through.
 
dtuuri said:
I'm trying to think through how "error bounds" apply to the 34:1 OCS of a typical glide slope. Why don't you guys enlighten me? :confused:
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Let's try the Socratic method: What's the slope of the glide path itself?










Need a hint? It's steeper than 34:1.
 
Ron Levy said:
Let's try the Socratic method: What's the slope of the glide path itself?

Need a hint? It's steeper than 34:1.
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No, I don't need a hint, I already gave you the answer here:

dtuuri said:
Being within specs is important, but on an ILS you should be following the glide slope. If the altimeter reads 75' too high, you'll descend below minimums that much before indicating DA, reducing the obstacle clearance. It doesn't mean you won't have any clearance at all, just less of it. How much less? If the obstacle clearance surface (OCS) is a 34:1 slope, the OCS is 88' at 1/2 mile, resulting in a normal clearance of 112' for a 200' DH. So if you drop another 75' on a 3° glide slope (20:1) you'll move about 1/8 mile [EDIT catch by ronachamp: "about 1/4 mile"] closer to the runway--about 1500'. The OCS gets lower, too, about 44' lower (1500 / 34) for a net clearance of 68', or almost twice the allowable altimeter error.


I get 112' of obstacle clearance at DH. See above.

dtuuri
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No charge for the gound school. :wink2:

dtuuri
 
dtuuri said:
No, I don't need a hint, I already gave you the answer here:


No charge for the gound school. :wink2:

dtuuri
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The error budget allows for flight technical error, altimeter errors, instrument errors (e.g., your CDI showing on-glidepath vs actually being on-glidepath).

I don't remember the error budget allocation (and it would take me a while to reconstruct it) for each error source.
 
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