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Greetings Mission Planners,

The Mission Planning System Support Facility has posted the main briefings from last month's Mission Planning Users Conference on their website at https://mpssf.hill.af.mil.  You'll need an account to download the files.  The briefings from the breakout sessions should be available soon.  

Many times folks need PFPS for ongoing operations but they don't have a current CD or know where to find one.  If you're on the SIPRNET (and if you really need PFPS you probably are) you can download PFPS 3.3 from the AFSOC Mission Planning Website on the SIPRNET at: www.afsoc.hurlburt.af.smil.mil/do/dox/doxc.  You'll also find links to the sites on the SIPRNET you'll need to update your threat database, download orders of battle and get current information (DAFIF, EChum, Aimpoints, digital charts and imagery) from NGA.

Are you an NGA employee who wants to help the war effort outside of a cubicle?  NGA is looking for employees to deploy in direct support of forces conducting operations in the Global War Against Terrorism.  This doesn't mean they'll put you on convoy duty with an M-60, rather you'll spend your time providing all that fancy "Geospatial-Intelligence" you can read about on the NGA website.  When you return home you'll have a greater appreciation of how your efforts benefit the warfighter and what the needs are in the "real world" - plus you'll  have a bunch of good stories you can tell in the bar.  If you're interested contact NGA's ODP (Office of Deployed and Externally Assigned Personnel).

One task NGA folks in the field do (that the rest of us can't) is use  Harris' Multi-image Exploitation Tool to convert current high resolution (cough) images into GeoTiffs for use in FalconView.  You can any type of imagery to the FalconView map stack, and no matter how current your CIB is there's always room for a picture taken yesterday.  Be careful converting high resolution images, the maximum resolution you want in FalconView 3.2/3.3 is 0.51 Meters.  Higher resolutions cause extreme performance degradation.  FalconView 3.3.1 fixes this problem and opens up the door for high resolution data sources like blueprints etc.

Mission Planning Tip:  PFPS Winds and Temperatures, Part II

See Part 1 at: PFPS Winds and Temperature Tool, Part I

I didn't expect to receive much feedback on downloading Winds and Temperatures, but I was wrong - several folks provided good information about planning with winds in general and in the use of the PFPS Winding Tool in particular.

Greg Spencer at Travis at Travis pointed out that the winds displayed for the T/O and Landing points are bogus - as you'll note below:

"The only sure-fire workaround is to enter the STTO and APPR points twice, then after winding, delete the duplicate STTO and APPR points. Another option is to use realistic points from a SID or STAR using appropriate (lower) altitude values. So if your second point would have an altitude of only 3,000 feet instead of 30,000 feet, the wind velocity entered in the STTO point would be much more realistic."

Of course another option is to ignore these winds.  In any case the new version of the Winding Tool (in test with PFPS 3.3.1) will provide a more accurate surface wind value.  Greg also explained that the OPARS winds used are only available every 1,000ft and the lowest altitude that winds are available for is 1,000ft (AGL).  This means that the 1,000ft winds are used from SFC-1,499 ft (approximately), the 2,000 ft winds are used from 1,500-2,499 ft and so on.  Your surface winds could be up to 1,000 ft off, but at altitude your altitude and the wind altitude will never be more than 500ft apart.

Finally Greg explained the "Climb/Descent Factor" on the configuration page:

If you enter 50% (the default) then for climbs and descents you'll use the winds at the 50% altitude, i.e. if you're climbing from 10,000 ft to 30,000 ft you'd use the 20,000 ft winds.  

Jim Evans (Lincoln NE, Forbes Field KS) points out that the Winding Tool has a disturbing tendency to save a route with a generic filename: "I discovered that before it applies the winds, the tool saves the route without asking you. If you're building a new route and haven't saved it yet, the tool saves it with whatever temp name CFPS is using, e.g., ROUTE1.RTE. Obviously, it's a good idea to save your route before you wind it."

Finally, Andy Marshall in Maine provided a good overview of why airspeed planning for an enroute leg isn't always an open and shut case.  While his example is for the KC-135E the same factors effect any aircraft at cruise

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A Few Notes on Range and Wind Effects from the…

-          When flying into a headwind, charted Best Range speed MUST be adjusted (increased.)

-          On time-critical missions, a speed higher than Best Range can be flown to optimize tradeoff between fuel burn increase and sortie duration decrease.

To compare the effects of various cruise speeds, let’s examine a KC-135E route from Bangor to Honolulu.  Let’s assume we’re limited to FL310 and a 165,000 fuel load.  Initially, we won’t include any wind.                                    

To add realism, let’s assume it’s winter and we’re bucking a 100 knot headwind all the way.  Bummer.  Let’s do the numbers again:

In the table above, you might note what appears to be a typo.  Into a headwind, by flying Optimum Mach instead of Uncorrected Best Range, we’ve saved two hours and burned virtually the same amount of fuel.  What’s just been demonstrated here is the concept of Winded Best Range, that is, you’ve got to fly faster into a headwind and slower with a tailwind.  Be assured that this is not a software bug – Boeing even says so. (Boeing Aero Magazine, number 12)  By crunching the numbers, we’ve found the KC-135 TAS correction to be about 20% of headwind (not to exceed Carson Speed!) and about 13% with a tailwind.  Interestingly, these corrections are darn close to those proposed in Stick and Rudder, circa 1944.

Let’s push up each of our profiles by 20 knots TAS (20% of the headwind) and watch what happens:

We’ve discovered several things in the numbers above…  One of them is that the suggested wind corrections to Best Range are just that – corrections that apply to raw Best Range alone.  If you’ve absolutely, positively gotta get the most range from a load of gas without regard to flying time, by all means, fly wind-corrected Best Range.  Knock yourself out.  In practice, pulling back the speed with a tailwind doesn’t matter much, but try it with software and see.

The most important lesson we just learned… Optimum Mach is both a target and a limit simultaneously.  In the KC-135 Mach .80 is the limiting airspeed.  Going any faster at any point in the profiles we’ve tried will cost more in gas than it will gain in speed. 

Among all the profiles we’ve looked at, the do-nothing alternative for coping with headwind seems the most attractive.  By flying uncorrected Optimum Mach we’ve damn near optimized both time and fuel, even into a headwind.  This has freed our minds to check the weather and think about Mai Tais and golf.

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Paul