TACAN Point to Point

MidlifeFlyer

Well-Known Member
This is for a future article I am thinking about. I'm familiar with Point to Point navigation. I even ended up doing it once on a flight without even thinking about it. What I am interested in is the history of it being removed from the Air Force Manual (and and any other military flight procedures). Here's what I have so far:

I have a copy of the October 2010 11-217 which describes TACAN point to point as a system to be used only under very specific circumstances "In order to legally conform to NAS area navigation procedures." The June 2019 version is even more limiting, requiring the pilot to say "unable" "unless the primary navigation equipment onboard the aircraft is certified for the appropriate area navigation capability."

The questions - and if you have access or can point me to the documents online, that would be a huge help:
  1. Is June 2019 the current version of the 11-217?
  2. Did the 2019 language appear earlier? When first?
  3. Is there a version earlier than October 2010 which limits the use of TACAN point to point? When?
  4. I have heard but have not been able to confirm that the limitation of TACAN point to point navigation was the result of a letter from the FAA saying it was illegal. I would love to get my hands on a copy of that letter.
Thanks.
 

MikeD

Administrator
Staff member
I don’t have the actual FAA verbiage, I’d have to look for something, but as a guy who did TACAN point to point many times, the FAA didn’t like the inaccuracy of it. The accuracy is fully dependent on the pilot doing it correctly and interpreting DME fall and rise correctly. That’s a lot of variables. When guys would do it incorrectly, they end up not going point to point, but instead intercepting a radial and then driving up or down that radial to get to the appropriate DME; which of course isn’t “direct” to the intended radial/DME. The whole purpose of point to point was as a poor-man’s RNAV mostly for tactical jets that were not RNAV equipped. But the inaccuracy, especially when used in areas where there may be Special Use Airspace restrictions existing, made its use/assignment/acceptance limited by ARTCCs

2019 should be the current version of AFM 11-217, as that large manual is only updated good number of years or so, with the latest revisions incorporating RNAV/GPS approach and enroute operations, which is something the earlier 11-217 and the 51-37, that I started with, didn’t have.

Curiously, I’ve never heard of a civilian interested in TACAN, much less point to point ops. That’s cool stuff.
 

Flyinthrew

Well-Known Member
I'll have to go grab some references, but I know it is still being taught in naval aviation training. Not as seriously as even just ten years ago, but it is definitely still there. In practice, I get sent direct to fixes that are defined only by a Tacan radial and DME almost every flight. My system is good enough that it is stupid easy, but it's still, strictly speaking, a Tacan point-to-point. The pencil to eyeball method was incredibly difficult.
 

///AMG

Well-Known Member
TACAN PTP was my baby in T-34s. It was probably just luck, but I could nail them pretty well on those BI/RI flights. Probably the reason I am here today :p
 

MikeFavinger

Hubschrauber Flieger
I thought AF pilots navigated point to point by intuition and gut feeling alone.

.

Seriously though, it seems like ATC interprets TACAN as an equipment code as being able to go point to point. I asked ATC one day why they kept giving me direct when I was filed with TACAN only and they said “I thought you guys could do that.”
 

MikeD

Administrator
Staff member
I thought AF pilots navigated point to point by intuition and gut feeling alone.

Seriously though, it seems like ATC interprets TACAN as an equipment code as being able to go point to point. I asked ATC one day why they kept giving me direct when I was filed with TACAN only and they said “I thought you guys could do that.”
Air to air TACAN is a great part of the system. One downfall is not being able to hold at VORTACs or TACAN stations.

Does the Army use it? I always thought they only used the VOR side of it.
 

Flyinthrew

Well-Known Member
I've filed Tacan only, and gotten direct for like 800 miles. Shrugged my shoulders and put my INS waypoint on the nose (the system lets me drop a bomb on a coffee table from 15 miles away, I think the waypoint is tight enough). I'm not sure they're acting as the gate keeper of navigational capabilities.
 

MidlifeFlyer

Well-Known Member
I don’t have the actual FAA verbiage, I’d have to look for something, but as a guy who did TACAN point to point many times, the FAA didn’t like the inaccuracy of it. The accuracy is fully dependent on the pilot doing it correctly and interpreting DME fall and rise correctly. That’s a lot of variables. When guys would do it incorrectly, they end up not going point to point, but instead intercepting a radial and then driving up or down that radial to get to the appropriate DME; which of course isn’t “direct” to the intended radial/DME. The whole purpose of point to point was as a poor-man’s RNAV mostly for tactical jets that were not RNAV equipped. But the inaccuracy, especially when used in areas where there may be Special Use Airspace restrictions existing, made its use/assignment/acceptance limited by ARTCCs

2019 should be the current version of AFM 11-217, as that large manual is only updated good number of years or so, with the latest revisions incorporating RNAV/GPS approach and enroute operations, which is something the earlier 11-217 and the 51-37, that I started with, didn’t have.

Curiously, I’ve never heard of a civilian interested in TACAN, much less point to point ops. That’s cool stuff.
Well, TACAN and it's VORTAC/VOR/DME counterparts. And yes, I'm certain it was about inaccuracy in a modern era of busy airspace.

The interest in point to point is mostly mine. I used to use VOR cross radials moving together to locate airports when I was a newbie pilot. It was an easy mental jump to use point to point one time when ATC gave me direct to a DME fix. I didn't even think about whether it was legal or not.

My current interest in the subject is related to MON and possible methods (technically acceptable or not) of accepting a more direct route, particularly when one of the MON VORs goes temporarily out of service.
 

Lawman

Well-Known Member
Air to air TACAN is a great part of the system. One downfall is not being able to hold at VORTACs or TACAN stations.

Does the Army use it? I always thought they only used the VOR side of it.
47G.

There are some guys that even use it to fly a DME Arc which is just weird given the other options in the cockpit.


Sent from my iPhone using Tapatalk
 

n57flyguy

Well-Known Member
This is for a future article I am thinking about. I'm familiar with Point to Point navigation. I even ended up doing it once on a flight without even thinking about it. What I am interested in is the history of it being removed from the Air Force Manual (and and any other military flight procedures). Here's what I have so far:

I have a copy of the October 2010 11-217 which describes TACAN point to point as a system to be used only under very specific circumstances "In order to legally conform to NAS area navigation procedures." The June 2019 version is even more limiting, requiring the pilot to say "unable" "unless the primary navigation equipment onboard the aircraft is certified for the appropriate area navigation capability."

The questions - and if you have access or can point me to the documents online, that would be a huge help:
  1. Is June 2019 the current version of the 11-217?
  2. Did the 2019 language appear earlier? When first?
  3. Is there a version earlier than October 2010 which limits the use of TACAN point to point? When?
  4. I have heard but have not been able to confirm that the limitation of TACAN point to point navigation was the result of a letter from the FAA saying it was illegal. I would love to get my hands on a copy of that letter.
Thanks.
Mark,

The 11-217 was rescinded and superseded by the AFMAN11-202V3, as of 10 June 2020. To answer your first question - no it is no longer current. As I recall, that language was not mentioned in the previous version of the 217. I might have an old paper copy in storage to cross reference, however I don't think it was limited prior to the 2010 revision. I am privy to that rumor as I had heard it wasn't a valid way to navigate any longer, but have no source document nor have I seen one.

More or less, last year in UPT it was vaguely discussed but rarely flown. I recall on two departure instructions we would get a FTF clearance where we were required to do the first two steps, then just fly it in the GPS once we were tracking properly to suffice the initial FTF principle which was the turn. I don't even know if that is still being used any longer.

Like you said, you do it without thinking about it. Whats taught is what can be quantified, and schwagging it based on ones internal clock while assessing rates of motion probably could be, but that research probably sitting in some dusty file box next to the Arc of the Covenant. So after you stab your eye with a pencil and break the HSI with your plum-bob and the problem is muddier then mud, then just know its now a thing of the past.
 
Last edited:

MikeD

Administrator
Staff member
Never used the pencil method, it never made much sense to me. I just basically visualized a plan-view of the HSI of “I’m here on the X radial for X mIles, and I want to go to X radial at X miles, what’s a good WAG heading?” Turn to that, and then analyze the DME as it would make its moves and refine from there.


I recall on two departure instructions we would get a FTF clearance where we were required to do the first two steps, then just fly it in the GPS once we were tracking properly to suffice the initial FTF principle which was the turn.
Another basic skill that isn’t taught anymore. It’s definitely nice to know. But, it, like many other things, is being hung up as no longer useful. Much like formation landings on the -38 side. Somehow deemed dangerous, after decades of successfully doing them.
 

n57flyguy

Well-Known Member
Never used the pencil method, it never made much sense to me. I just basically visualized a plan-view of the HSI of “I’m here on the X radial for X mIles, and I want to go to X radial at X miles, what’s a good WAG heading?” Turn to that, and then analyze the DME as it would make its moves and refine from there.
It makes sense after you do what you did, so why use it to begin with is what I say. Explaining it is more confusing than actually doing it.

Another basic skill that isn’t taught anymore. It’s definitely nice to know. But, it, like many other things, is being hung up as no longer useful. Much like formation landings on the -38 side. Somehow deemed dangerous, after decades of successfully doing them.
It certainly helps expand SA even if you are not doing true FTF at all. We can draw out the pattern in the anchor by inputting the points, but knowing them along with a backup navaid can be useful, if only for SA.

I can't speak for the 38 formation landings - I suppose the assumed risk is now considered too great or the skill no longer applicable.
 

Space Monkey

Well-Known Member
Air to air TACAN is a great part of the system. One downfall is not being able to hold at VORTACs or TACAN stations.

Does the Army use it? I always thought they only used the VOR side of it.
Hold a VORTAC/AN?? Was that ever possible??
 
Last edited:

MikeD

Administrator
Staff member
I can't speak for the 38 formation landings - I suppose the assumed risk is now considered too great or the skill no longer applicable.
The FTF is a good skill as it comes to basic navigation and understanding DME relations to different radials at different distances, even if they aren’t used as a specific function anymore.

Form landings have been deemed dangerous after a recent form landing accident of a T-38 when the IP screwed up a recovery after a student error. There’s much gained in not only airmanship, but practical application, with formation landings. There been no trend of them as accidents. If you want an accident trend, we’ve packed more T-38s into the dirt in the final turn than anything else with that jet. Yet we still fly overheads. Standard USAF overreaction, and with the CAF by saying form landings are prohibited with the newest fighters. Just more watering down of the pilot quality process.
 

n57flyguy

Well-Known Member
The FTF is a good skill as it comes to basic navigation and understanding DME relations to different radials at different distances, even if they aren’t used as a specific function anymore.

Form landings have been deemed dangerous after a recent form landing accident of a T-38 when the IP screwed up a recovery after a student error. There’s much gained in not only airmanship, but practical application, with formation landings. There been no trend of them as accidents. If you want an accident trend, we’ve packed more T-38s into the dirt in the final turn than anything else with that jet. Yet we still fly overheads. Standard USAF overreaction, and with the CAF by saying form landings are prohibited with the newest fighters. Just more watering down of the pilot quality process.
That is exactly my sentiment - the minds perception of time and space.

I recall that at Vance, friends of mine knew the student. The decision to remove formation landing seemed kneejerk to me but I didn't get the full wash on what had happened. I assume they got rid of them in the T6 as well, I never did them as my track was T1. When I got to UPT the syllabus was already changed. A third or more sorties cut.
 
Top