VOR Tests

mhcasey

mhcasey

Well-Known Member
Does an airborne check need to be done on a victor airway? The FARs seem to pretty clearly indicate yes, but my chief flight instructor has been telling me to just do them over the airport (not on an airway) because on the ndb (on field) approach chart there is a published radial from the nearest VOR, and since it's published, we can use it.
 
Pretty sure it has to be on the airway.

I would think that the published route on an approach could be an acceptable method since it is published and you will know what position you are over the runway, NDB, etc.


§ 91.171 VOR equipment check for IFR operations.

(a) No person may operate a civil aircraft under IFR using the VOR system of radio navigation unless the VOR equipment of that aircraft—
(1) Is maintained, checked, and inspected under an approved procedure; or
(2) Has been operationally checked within the preceding 30 days, and was found to be within the limits of the permissible indicated bearing error set forth in paragraph (b) or (c) of this section.
(b) Except as provided in paragraph (c) of this section, each person conducting a VOR check under paragraph (a)(2) of this section shall—
(1) Use, at the airport of intended departure, an FAA-operated or approved test signal or a test signal radiated by a certificated and appropriately rated radio repair station or, outside the United States, a test signal operated or approved by an appropriate authority to check the VOR equipment (the maximum permissible indicated bearing error is plus or minus 4 degrees); or
(2) Use, at the airport of intended departure, a point on the airport surface designated as a VOR system checkpoint by the Administrator, or, outside the United States, by an appropriate authority (the maximum permissible bearing error is plus or minus 4 degrees);
(3) If neither a test signal nor a designated checkpoint on the surface is available, use an airborne checkpoint designated by the Administrator or, outside the United States, by an appropriate authority (the maximum permissible bearing error is plus or minus 6 degrees); or
(4) If no check signal or point is available, while in flight—
(i) Select a VOR radial that lies along the centerline of an established VOR airway;
(ii) Select a prominent ground point along the selected radial preferably more than 20 nautical miles from the VOR ground facility and maneuver the aircraft directly over the point at a reasonably low altitude; and
(iii) Note the VOR bearing indicated by the receiver when over the ground point (the maximum permissible variation between the published radial and the indicated bearing is 6 degrees).
(c) If dual system VOR (units independent of each other except for the antenna) is installed in the aircraft, the person checking the equipment may check one system against the other in place of the check procedures specified in paragraph (b) of this section. Both systems shall be tuned to the same VOR ground facility and note the indicated bearings to that station. The maximum permissible variation between the two indicated bearings is 4 degrees.
(d) Each person making the VOR operational check, as specified in paragraph (b) or (c) of this section, shall enter the date, place, bearing error, and sign the aircraft log or other record. In addition, if a test signal radiated by a repair station, as specified in paragraph (b)(1) of this section, is used, an entry must be made in the aircraft log or other record by the repair station certificate holder or the certificate holder's representative certifying to the bearing transmitted by the repair station for the check and the date of transmission.
 
Thats what I answered before I edited the post also. The next description part of the question is what got me.

It isn't on an airway
It isn't published in an AFD

I was going to go a little more in depth about it then, 'no it doesn't have to be on an airway'.
 
Do a dual check. If I read the FAR correctly you can do the dual check anywhere (assuming VOR in reception range)
 
Alright I'll clarify.

1 VOR
No VOT, no ground checks, no airborne (published) anywhere close
Only option left if random airborne...FARs say find a spot along the center of an airway decently far away and at a decently low altitude...

My Chief Instructor says "no it just needs to be published. The approach clearly identified the airport (more specifically the ndb on the field) to be off of the 331 radial for 20 miles...just use that."

Makes sense to me. You could pretty easily misidentify a radial by just trying to trace it on the map. They want you to use airways because it's pretty clear whether or not your ground checkpoint is underlying that airway. But the FARs specify it should be an airway, not just any published feeder route or identification radial.

Legal?
 
Yeah thats what I thought you were trying to get into.

As I think about it more a published radial is not exactly a published route so that where I think it might get sticky.
 
Are we talking about using this part of the reg?

==============================
(4) If no check signal or point is available, while in flight—

(i) Select a VOR radial that lies along the centerline of an established VOR airway;

(ii) Select a prominent ground point along the selected radial preferably more than 20 nautical miles from the VOR ground facility and maneuver the aircraft directly over the point at a reasonably low altitude; and

(iii) Note the VOR bearing indicated by the receiver when over the ground point (the maximum permissible variation
==============================

If so, the words seem pretty clear. What's the question? Illiterate chief flight instructor or does he mean somehting else entirely?
 
That part exactly midlife. "Established VOR airway..." Can a radial used for identification purposes fall under "established VOR airway." Again, the radial in question is published on the NDB approach to identify the NDB. It is not a transition route or a victor airway.
 
I would say the FAR spells it out very clearly. I doubt anyone would ever bring a VOR check into question but it is hard to argue the regs when it explains the requirement for a single VOR airborne check.
 
mhcasey said:
Does an airborne check need to be done on a victor airway? The FARs seem to pretty clearly indicate yes, but my chief flight instructor has been telling me to just do them over the airport (not on an airway) because on the ndb (on field) approach chart there is a published radial from the nearest VOR, and since it's published, we can use it.
Click to expand...

to follow regulations, as has already been pointed out, you may use a published afd airborne checkpoint or as from part 91.171:

(4) If no check signal or point is available, while in flight—
(i) Select a VOR radial that lies along the centerline of an established VOR airway;
(ii) Select a prominent ground point along the selected radial preferably more than 20 nautical miles from the VOR ground facility and maneuver the aircraft directly over the point at a reasonably low altitude; and
(iii) Note the VOR bearing indicated by the receiver when over the ground point (the maximum permissible variation between the published radial and the indicated bearing is 6 degrees).

my primary airport has no ground receiver checkpoint, so i use the dual-receiver check almost 100% of the time unless i'm working in a single-vor aircraft. these folks could find themselves 'legally grounded' when requiring an ifr departure clearance past 30-days. i currently have only one instrument student with a single vor unit. :bandit:
 
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