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The SpaceX Falcon 9 rocket rises above the lightning masts on Space Launch Complex 40 at Cape Canaveral Air Force Station, carrying the Dragon resupply spacecraft to the International Space Station. Liftoff was during an instantaneous window at 3:25 p.m. EDT on Friday, April 18. Dragon is making its fourth trip to the space station. The SpaceX-3 mission, carrying almost 2.5 tons of supplies, technology and science experiments, is the third of 12 flights under NASA's Commercial Resupply Services contract to resupply the orbiting laboratory. > Read more Image Credit: NASA/Kim Shiflett
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The Grand Tour: Fuel Planning

As I mentioned in my last entry (/2014/04/11/schedule-route), I knew I would need at least one intermediate fuel stop on this trip. Where to stop for fuel?

In the old old days (I know: there are lots of pilots flying now who were flying long before I was: for them, the old old days are the 50s, 60s, and 70s, not the 80s, and 90s), before the Internet, we had paper charts (VFR—i.e., visual—charts from the FAA, IFR—instrument—charts from the FAA and, in my case and the case of many others, from Capt. Jepp), the Airport and Facilities Directory (A/FD), and various private guides. I used all three for flight planning back then, along with the performance and fuel consumption information from the pilot’s operating handbook for the airplane I was flying. The POH, in conjunction with winds aloft forecasts, told me how fast I’d likely be flying and how much fuel I’d burn each hour. The POH also gave the fuel tank capacity information, and the maximum weight the airplane could safely carry. On a flight across the country in the past, I’ve flown alone or with one person—this time, I expect to be alone—and even with my Mooney’s limited load-carrying capabilities I’ll be able to fill the fuel tanks.

Take the fuel available (in this case, 75 gallons), the fuel burn, the desired fuel reserves (I want at least an hour’s fuel in my tanks when I’m planning to land, even if I have to go to an expected alternate airport for some reason), and I find the time I can fly. Yes, I have to take into account differences in fuel flow under different flight conditions: for example, my Mooney burns about 23 gph while climbing, 11.4 gph in cruise. Include the probable winds at the expected cruise altitude and the true airspeeds in climb and cruise and the result is ground speed; couple expected ground speed with duration and that yields the airplane’s planned range. Oh, airplane can fly six hour legs, let’s say, and your sitzfleisch can only handle four? Use four hours in the planning! But, I’ve always been happy to fly for as long as my airplane will.

(Incidentally, even in these new days, all this information is needed, because I need my airplane’s range to determine the universe of potential fuel stops.)

Now, I can actually start looking for an airport. How many fuel stops would I need? For example, if I’m flying 2,000 nm and I have an 800 nm range, I’ll need two stops; make that range 650 nm, and I’ll need three stops. Going 1,000 nm with an 800 nm range? I can chose any airport starting 200 nm from departure, up to 200 nm from destination. Longer airplane range as a percentage of the leg to be flown means more flexibility—more choices, but more airports to evaluate.

Let’s take the trip at hand: KPAO (Palo Alto) to KGTU (Georgetown, Texas, near Austin): 1,277 nm airport-to-airport along the great circle route. Unfortunately, the great circle route goes through airspace that’s restricted—not available for civilian use when the military is using it. The great circle route from KPAO to KGTU goes right through pieces of the Edwards military complex (R-2508) and the White Sands Missile Range (R-5119 and the parts of the R-5107 complex). The obvious change of dodging Edwards to the north takes me through some of the Nellis-Tonopah areas, also off limits. Some restricted areas in the U.S. are off-limits only some of the time, but Edwards, White Sands, and Tonopah are in use either continuously, or weekdays during, roughly, daylight hours. (I have flown through the Edwards complex—one Sunday, in fact, was able to fly right over Edwards AFB—but I won’t plan on that!)

My working route: KPAO VINCO KENNO DYSSS JUPTR LLO KGTU (Palo Alto airport to the VINCO intersection—a point in space near San José—then on to KENNO and DYSSS intersection to dodge Edwards and Nellis-Tonopah, JUPTR intersection to avoid White Sands, Llano VOR [a radio navigation aid], and in to Georgetown). That jog at LLO is to enter the Austin terminal are from a local point, rather than from some arbitrary point hundreds of miles away. This helps with traffic management and flow.

How does all of this affect fuel stops? The zigs and zags around these restricted areas mean more distance to fly, and decrease effective range. In this case, the distance to be flown increases from 1,277 nm to 1,297 nm, a mere 2% increase. Because of the long distance I’ll be flying and my being able to plan the zigs and zags so they create the longest possible triangle (view this triangle’s other sides as the direct route, and flying right up to the edge of the restricted airspace before turning to avoid it), I can minimize the increase in distance.

Rounding, I’m left with a 1,300 nm trip. My Mooney has a bona fide in-flight duration of five and a quarter hours with a reasonable reserve. Planning conservatively eastbound, I’ll have a 200 knot ground speed, and a 1,050 nm range. I won’t be surprised, though, to get a 20 knot tailwind at 25,000′, but I’ll treat that extra 100 nm as reserve (and possibly use it en route to change my planned fuel stop, as I did in 2011 when flying westbound to eliminate a planned fuel stop). Generally, I plan on no tailwind and 25,000′ when eastbound, and a 20 knot headwind and 12,000′ westbound.

Back to planning the fuel stops. With a 1,300 nm flight and a 1,000 nm range, I have an enormous number of possible fuel stops: get me 300 nm from home, and I can start looking for gas, and I can keep looking for gas until I’m 300 nm from Georgetown. Generally, though, I like to split the flight up into roughly even chunks. In this case, 1,300 nm will take about 7 hours, including climbing to altitude (climbing covers ground more slowly than cruising), so I’d really be looking for a fuel stop about 3-4 hours into the flight.

One of the problems flying over the desert southwest is there aren’t many people, so there aren’t many towns, so there aren’t many airports, so there aren’t many fuel stop options. One of the nice things about flying over the desert southwest is there aren’t myriad options for fuel stops, so it’s easier to consider the choices. I like to avoid big-city airliner airports like Las Vegas, Phoenix, and Flagstaff. I need a runway long enough for safe operations: minimum 2,300′ feet at sea level, increasing with altitude (and heat, definitely a factor in the desert in June!). Most of the airports in the desert southwest that have gas will have a long enough airport. Oh, I also want a paved runway: my Mooney doesn’t do well on dirt or gravel, and I’d rather stay off grass.

I’d also like an instrument approach available at my planned fuel stop, in case something comes up and the weather turns a bit bad. Though perhaps unlikely in June along this route, it’s a nice additional safety net, a built-in Plan B.

Reviewing the charts out at 600-800 nm from Palo Alto shows I’ll be around Flagstaff, Winslow, St. Johns, Taylor, and Show Low, Arizona, Santa Fe and Belen, New Mexico, and places like that. In the old days, this is where those airport guides came in: you could find out what FBOs (effectively, in this case, airplane gas stations) were at each airport and phone numbers for those FBOs. You could call the FBOs and ask about their gas prices, whether they had a phone available (no cell phones back then!) so you could call for an update on the weather, and things like that. Back in the old, old days, that’s what I did, too.

I would now have the desired course, dodging all the restricted areas, and the possible fuel stops I’d like to consider (those around mid-flight, in this case). I’d like to find a fuel stop right along my planned flight path, or at least not very far from it. From the compiled list, I’d chose a probable stop, and a couple of alternates.

Today, we have many more tools available. The first one widely available once the Internet came out of the research closet and the Web became a marginally widespread reality, was AirNav. This site, started in 1996, gives pilots a bunch of valuable navigation information, including airports, FBOs, and even pilot comments and reviews! One of the brilliant pieces of AirNav is its fuel stop planner: the Web site’s code logic and database take care of the tedium of checking allll the airports along a route for fuel prices and distance from the direct course. Though it doesn’t allow for route entry—I tell AirNav my departure and destination airports and it assumes a great circle route—it certainly simplifies fuel stop planning. Right there in front of me, with just a little bit of work, I have 10, 20, even 50 possible fuel stops for my trip, along with total distance (again, assuming great circle routes between airports) and fuel prices at each airport. (AirNav gets its fuel information from users, among other sources.)

A few years ago, I wrote about ForeFlight, a flight-planning and in-flight iPad app. That’s another tool I use for flight and fuel stop planning. Ditto Enflight, a flight planning and weather briefing tool on the Web. Enflight gives me better actual operational estimates of things like total fuel burn, duration, and range (ForeFlight uses just one fuel burn rate and speed for a flight, and Enflight uses the actual flight characteristics of my airplane, taking into account the slower speed and higher fuel burn during climb, for example).

Taking all of the information, tools, and techniques into account, I’m currently planning on St. John Industrial Air Park in St. Johns, Arizona—KSJN—for my stop. Here’s AirNav’s info on this flight (KPAO-KSJN-KGTU), complete with a point-to-point great circle route depiction (not the route I’ll be flying, remember).

What about alternatives for the fuel stop, in case something goes wrong? And alternate routes, in case of weather (which can completely derail all the fuel stop planning)? More to come.

The Grand Tour: Schedule, Route

After determining the general framework—to Austin, Syracuse, Boxborough, Palmyra, Boulder, and home—I started looking at nearby airports. In some cases, this is easy: Syracuse, New York has Hancock International, for example. Though KSYR isn’t my favorite airport—I’d rather go to a little airplane airport than a big airplane airport, because typically the fuel prices are lower and those who run the airport tend to take better care of us little airplane folks—KSYR is the closest airport to my folks’ place, and that’s where I’m headed. On the flip side, a big airplane airport almost always has great instrument approaches full runway and approach lighting, and long runways, which come in handy when the weather’s bad (i.e., rain, low clouds, very low visibility).

Boulder Municipal is another obvious choice, except that there are no instrument approaches to KBDU. If the weather goes down, I’ll have to land elsewhere (e.g., Vance Brand Field [KLMO] in Longmont, or Erie Muni [KEIK] in Erie, or Rocky Mountain Metro [KBJC, what we used to call Jeffco]). It won’t be as convenient, but it would still be a far cry better than Denver Int’l!

The decisions, then, based on where those on my team live and work, where my parents are, etc., are

  • KGTU, Georgetown, Texas (near Austin)
  • KSYR, Syracuse, New York
  • 6B6, Stow, Massachusetts (near Boxborough)
  • 57C, East Troy, Wisconsin (near Palmyra)
  • KBDU, Boulder, Colorado

These represent leg lengths of 1280, 1272, 206, 746, 777, and 806 nautical miles, respectively (including the trip home to KPAO). The first two of these are too long. Roughly, I can figure on about five and a quarter hour legs given fuel of 75 gallons and my desired reserves. Here are the parameters:

  • high-power cruise
  • FL250 (25,000′)
  • climb from sea level
  • 1 hour reserve
  • 11.4 gph in cruise
  • 23 gph in climb
  • about 40 minutes of climbing time

This gives me roughly 84 gallons used in a no wind situation, 77 gallons with the winds forecast for right now (as I write this) for the KPAO-KGTU leg. Nope: too much fuel. I need a fuel stop.

How to find a fuel stop? Where to stop, how long should the legs be, how far from my ideal route will I want to, or have to, divert? Many questions, including the implicit one: how do I choose an exact route?

More to come.

The Grand Tour: Concept

Forty years ago late this spring, I graduated from high school, the Manlius Pebble Hill School (aka MPH). My alma mater is honoring me with this year’s Commencement address.

I very much enjoy flying out to the east coast on my own wings. I don’t do it often, sometimes because of the more difficult vagaries of the weather patterns, sometimes because of my schedule. (I have made the flight across the country, eastbound, in one day—in fact, setting a national record and world record that still stands. It’s a grueling day, and not just because of its duration aloft. Taking two days eastbound is much easier, and two days for the westbound trip is almost mandatory because of the prevailing winds.) This time, though, the climate patterns in early June tend to support making such a trip, and I have the time to do it.

In part, the time to make the trip on my own wings is thanks to the geographic distribution of the US members of my team at work: Texas, Massachusetts, Wisconsin, and Colorado, in addition to here in the Bay Area. The eastbound flight will be from Palo Alto to Austin, Texas, then up to Syracuse, New York for Commencement. After Commencement, I head east (!) to Boxborough, Massachusetts, then to Palmyra, Wisconsin and Boulder, Colorado before returning home. Though there is always the possibility of nasty weather that’s so bad it cannot safely be penetrated nor feasibly circumnavigated, the chances of that in early June tend to be low. To play things safe and give me time to respond cogently to weather or mechanical delays, I’m planning to arrive in Syracuse on Thursday, with Commencement scheduled for Sunday.

Planning a trip like this takes a lot of thinking: watching the weather patterns, determining primary and alternate fuel stops, figuring out exactly where to land (there are a bunch of airports in the Austin area, for example: nothing says I need to land at KAUS, Austin-Bergstrom airport, where the airlines go!). I’ll record some of those planning thoughts here.

Good Night, Sky

I kissed the sky good night.
She had courted me, and I her.  Weaving around each other, wheeling, gliding, caressing, inviting.

Beckoning—yearning.

It was time.
I prepared.  She waited, always ready.
Tonight, lovely as ever.  Dark, but not mysterious.

We had not long together.

I delivered my kiss.
She responded, in kind.
Not once, not twice, but more.
Then, done.

We went to sleep, happy, content, knowing.
Knowing we would kiss again—
but knowing not quite when.

Pete

He was unique.

Pete Seeger’s career spanned something between 50 and 70 years, depending on when you figure he retired (if he ever really did).  He sang, he protested, he sang, he inspired, he sang, he engaged in activism.  And he sang.

Pete had a knack for getting a crowd singing, better than anyone else I’ve ever seen: better than Arlo Guthrie, better than Peter, Paul, and Mary, better than Joan Baez, better than anyone else.  And not just singing, but singing well.  And not just singing well, but singing harmony!  He’d teach the harmonies as he went, he’d bring in the basses, and the sopranos, and everyone in between, and he’d have parts for us all.  If you weren’t comfortable singing a part, well, just sing melody in whatever range you can.  Sing, sing joyously, ’cause Pete did, and he brought out our best.

My favorite concert of his: a freebie, at Stern Grove in San Francisco, in the early ’80s with my cousin and some friends.  It wasn’t San Francisco weather, though: it was summertime, and it was sunny, and it was hot!  Wow, was it hot.  But, we listened, and we applauded, and we sang and sang and sang.

Thanks, Pete: for singing, for inspiring, for having a hammer, for helping us find the flowers, for making a difference.

First Flight of the Year

It had been a couple of months since I’d flown.  The airplane had been in for its annual checkup since just after Thanksgiving, and I had to scrub planned flight in a taildragger with one of my favorite instructors earlier this week.  With the airplane’s return from maintenance just the day before, I was looking forward to the sky.  The weather had been unseasonably (and unreasonably) mild: clear skies or high overcast, very calm winds, springtime warm.  I wanted to fly!  I was ready: I was really ready!

During the annual, we replaced the #2 nav-comm radio, and I wanted to get familiar with it, see how it performed, etc.  I also wanted to do some good air work: slow flight, steep turns, stalls, coordination maneuvers, and some pattern work.  I wanted to fly!  I was ready: I was really ready!

Greasy Nose Gear

Greasy Nose Gear

Alas, I was not really ready for what I found.

Take a close look at the picture on the left.  This is the airplane’s nose wheel.  (It might be valuable to realize that the maintenance shop that performed the annual inspection had washed the airplane just before delivery.)  See those very dark gray, nearly black radial streaks emanating from the hub?  I did, too.  And I really didn’t want to see them!  Since they were there, though, I did want to feel them.

Grease.

Nose Gear Hub

Nose Gear Hub

Why is there so much grease on the hub cap?  Where did it come from?  Is it safe to fly?  (Well, sure, it’ll be safe to fly: but maybe not to land!)

After confirming that the local maintenance shop was closed, I removed the three screws securing the hub cap.  It seemed like things were not in good order: grease, and what appeared to be a loose ring of some sort.  Nope: not flying today.

Feh.

I wanted to fly!