TPC charts

[AlphaMikeFoxtrot]

Ok.. I know that I should know this one, but my memory has slipped me and I can't track down the answer anywhere. How is the elevation derived for the min altitudes in each sector on the TPC chart? I know that an actual chart has this posted in the legend, but seeing as how we rely totaly on CFPS I have no actual charts. Any help would be great!

[Guest KoolKat]

"The Maximum Elevation Figures shown in quadrangles bounded by tickled lines of latitude and longitude are represented in THOUSANDS and HUNDREDS of feet above mean sea level. The MEF is based on information available concerning the highest known feature in each quadrangle, including terrain and obstructions (trees, towers, antennas, etc.)"

Rounded up to the nearest hundred, of course.

There is certainly no good reason to memorize/remember anything that you can look up on a legend.

BENDY

[backseatdriver]

I know that an actual chart has this posted in the legend, but seeing as how we rely totaly on CFPS I have no actual charts.

Your squadron doesn't have real charts at all? No self-respecting nav should have ever allowed that to happen.

[ 08. February 2006, 18:17: Message edited by: backseatdriver ]

[Guest KoolKat]

Ha..your a nav, I didn't realize that before.

Of the many unneccesarily memorized things you have, that probably should have been one of them.

Regardless, I, a pilot, grabbed an old TPC out of my closet and copied it off the legend.

How you don't have a chart as a nav lying around somewhere, or AT LEAST a book or something that had that info in there, I have no idea.

But, alas...just asking someone else the answer is just as proven technique as looking at the display yourself. Assuming you get the correct answer.

"Hey Nav, what's my drift?"

BENDY

[FireMission]

Here's how it's done:

Maximum Elevation Figures (MEF) are computed by the National Imagery and Mapping Agency (NIMA) and take into account both terrain and obstacles.

If the highest feature within a latitude/longitude grid is terrain, NIMA adds 200 feet to elevation, plus the vertical accuracy of the identified point. This value is then rounded to the next 100-foot value.

If the highest vertical obstruction (man-made) is higher than the highest terrain elevation plus 200 feet, then the MEF is computed using the elevation of the obstruction plus its vertical accuracy, then rounded to the next higher 100-foot value.

What is critical to keep in mind is that the MEF may give over 200 feet or less than 50 feet of clearance, and does not ensure absolute clearance of terrain or obstacles.

for example: 3^1 means the highest feature within that grid is between 2901 and 3000 feet.

[Guest KoolKat]

Finally, someone with a book. :rolleyes:

BENDY

[FireMission]

Yup

[AlphaMikeFoxtrot]

Thanks for the speedy responses... I knew I could count on this forum for the answer.

Now I feel like I need to explain myself. 1) I am currently deployed, so that should explain the no charts/ books readily available 2) I'm a nav on the Buff, and its seldom that we fly low... you ask me about a JNC I could probably tell ya 3) back home we have access to "actual" charts through base ops, but really no need for them

Now I would like to say that those who contributed can add this to your OPR... handselected to aid in the identification of dangerous terrain to sustain B-52 operations over the Stan.. or something along those lines.

In all seriousness.. thanks guys!

[busdriver]

who the hell actually uses TPC's? We should just dump the damn things and use sectionals.

[Guest SpectrePilot]

I second that. TPC's are the most outdated POS's in the world. OK, at least in the USA... I know we gotta train like we fight, but when it comes to flying training low levels in the continental US, where topography and obstructions are changing so fast, I would feel SO much safer with an up-to-date Sectional in my hand. (And guess what? We just discovered today that PFPS will overlay your route on a SECTIONAL instead of a TPC if you click on that option! But, we can't use it... Nice, huh?)

[HuggyU2]

Originally posted by busdriver:

who the hell actually uses TPC's? We should just dump the damn things and use sectionals.

Can I get an "Amen" to that, brothers!!!

[Guest Navtastic]

Originally posted by gearpig:

Right. I want the first time my Nav ever sees a TPC is in the desert when he can't figure out where the Bagram sectionals are.

My thoughts exactly.

[Guest Hydro130]

"2"

I love/hate/it/that like the rest of you, but TPCs are a fact of life for the time being (let's not start a "what's out-dated in the USAF" thread -- useless, I spent 10 years trying), so go get smart on 'em.

Cheers, Hydro

[ 09. February 2006, 13:07: Message edited by: Hydro130 ]

[busdriver]

I guess the JOG is a bit small of a scale for some of you flying "low level?" I don't really see much of a difference between a TPC and a sectional, if your brain is used to reading 1:500, whether you're using a TPC or a Sectional shouldn't really matter. To delve into that what I would do if I ruled the world area, why not produce sectionals for our overseas areas, with modern technology, it wouldn't be hard to keep them updated.

[dmeg130]

We typically use JOGs for all our low-level route charts. There are some cases where TPCs are nice due to size, terrain shading, etc. We do carry sectionals as well, but don't normally use them for LL.

PS: JOGs are larger scale (1/250 v 1/500). Sorry, just semantics. Stupid geography degree...

[Nanook]

Geez, it's weird hearing of a BUFF nav talking about not flying low much. That's all we did my first few years in the mighty eight engined behemoth. There was a low level, IR-476, in the STRC (Montana) that was 3.5 hours long and most were 2-3 hours. Red Flag's hard deck was 100 ft and the FBs flew below us. All the navs were responsible for keeping up the low level charts for the squadron and each flight was assigned four or five. We would sit on alert and chop up thousands of TPCs to make 80-100 copies of each chart for every copilot and each nav/RN in the squadron. Then, horrors, we would have to actually CHUM each chart. You gotta love FalconView.

[AlphaMikeFoxtrot]

Don't worry Nanook, it appears they are trying to bring back the LL mission to the BUFF. It is a slow start at it doing Shows of Force at 5k AGL, but it appears that its working and they like us lower and lower. We'll see what the future holds, especially if they cut the BUFF force by 20 or more a/c. As you probably know LL is tough on the airframe, with less to work with things could get fun.

[busdriver]

With the BUFF switching to more stand off munitions, what's the point?

[Guest ShadowNav090]

Unfortunately, that's all we have in the pacific. TPCs and JOGs. Sometime the host nations have better charts... Yay for E-chum!

-Rev 17

[Guest Hydro130]

Rev --

Is D Barker still y'alls PFPS guy at RODN?

That is one all-kindsa-hella good dude...

Cheers, Hydro

[ 16. February 2006, 17:48: Message edited by: Hydro 130 ]

[Guest ShadowNav090]

Hydro,

Yes he is, I am our squadron's PFPS Rep. He can do amazing things with those machines. He is a great guy. He got remarried recently. Rumor has it he is trying to have kids again!

-Rev 17

[Guest Hydro130]

Rev,

Cool, I worked with him on a BALANCE TORCH a while back -- great guy...

If you ever need help from "upstate" (Yokota), Terry Mallon is 'The Man' -- another great guy who is ALL about supporting the mish (plus, his name *might* be familiar around RODN from his past life) ;) ...

Let him know if you need anything, and tell him Hydro sent you :D

Hydro

Edited for spilling again...

[ 16. February 2006, 18:37: Message edited by: Hydro 130 ]

[AlphaMikeFoxtrot]

B Driver... if you consider 7 miles standoff then yeah thats the way we're heading. if you're referencing JASSM, thats just filling a role that is already there (ie CALCM). The wave of the future for the BUFF is SDBs. There's not much standoff capability there... plus some of the other gravity driven winged variants will only take us out to a 30 mile release. When I think standoff I think in the hundreds. Anyway, the point is, Shows of Force and Presence Routes are big right now. I guess its a kinder gentler AF. That said, the BUFF is going lower and lower.

[Bergman]

Originally posted by AlphaMikeFoxtrot:

That said, the BUFF is going lower and lower.

So, how low is low? This low....?