Sunday, June 4, 2023

Why Does Piet Fly So Slow, Mifflin Day 2


Day 2 was a classic "Mifflin Day", with suitably strong winds from the north. The shape of the mountains in this area favor a task that goes to the north and east of the Mifflin airport.  The task for day 2 was: 

Start44Start D
-1Honey Grove10.0
-35Shade Mtn10.0
-9Mill Creek15.0

Here's a map overview of all the gliders that flew in the 20m multi-seat class: 

The turn areas are indicated as large red circles. QQ is in dark red, and the winner for the day, Hotel-Hotel is in cyan.  I ranked a terrible 12th for the day. The only competitors who did worse than me were Hotel-Seven and Four-Delta.  Hotel-Seven landed at Selingsgrove (just next to the Susquehanna river) and Four-Delta motored home. When I saw my place on the scoresheet, I couldn't believe how poorly I ranked for what I thought was a good flying day.  Let's figure out where I went wrong. 

Piet's Flight Narrative:

I started as soon as we were allowed.  I started at the most southerly part of the start line as I could, at the highest altitude I could make.  I headed straight to Shade Mountain.  KS flew along my left wing, faster, and got to Shade Mountain first.  He had a much higher speed along the ridge than I did, but we ended up getting to the turnpoint at Shade Mountain at about the same time.  We connected with a strong thermal, and made the jump over the Susquehanna River.  KS was much further ahead than I was. 

You can see the gliders following KS and me as we head toward the Susquehanna River.  This is before we climbed in a thermal.  This part of the mountain isn't as good for ridge soaring, so our ground speed had to slow down significantly at this part of Shade Mountain. 

I turned around about five miles too early.  Karl was much further ahead of me on the Northumberland mountain, and turned around at about the same time. I think I lost about 8 miles total distance by turning around early.  I'm not sure why I turned around here.  In retrospect, I should have gone further.  Looking at all of the other traces, everybody turned around about the same place Karl (KS) did. 

When we tried to jump back across the river, a traffic jam formed up.  Many of the gliders that were behind me started to pile up near the river.  We all struggled to find enough thermal.  I headed out early, and found a strong thermal right over the river. (Yeah, this doesn't make sense to me, either). 

There I am, escaping over the river, while others are still struggling
There I am, escaping over the river, while everybody else struggled to gain height

Once I climbed on that thermal over the river, we had plenty of altitude to make it back to Shade Mountain.  I asked my copilot to fly straight and level while I tried to take off my jacket.  I could not take off my jacket. In order to keep from overheating, I took a mouthful of water and spat it onto my chest. The jacket struggle is real! 

I flew down Shade Mountain until the direction of the wind didn't look very favorable with the direction of the ridges.  Right around Lewistown, PA, Shade Mountain takes a turn to the left, no longer perpendicular with the northerly winds.  My flight computer was showing winds of 035 at 8 knots.  In retrospect, the other flight computers of the competitors showed more like a 360 at 18 knots. Maybe I need to tune the HAWK variometer's wind parameters.  At any rate, my early turn-around cost me between 10 and 12 miles, depending on where each competitor turned around. 
QQ (in red) turned around just after getting into the circle.  Everybody else went further.
QQ can be seen at the top right of this map

The third turn area was Shade Mountain, 10 mile radius. You might see a pattern here. Of course, I turn early.  The pack following behind me turned much later. I cheated myself out of another 10 miles. The distance isn't that important, but the fact that I'm covering these distances at 80-100 knots means the opportunity to raise my average velocity is lost when I turn early. 

The final turn area was along Jacks Mountain.  As you can guess, I turned earlier than everybody else.  I turned almost 7 miles earlier than everybody else did.  This cheated me out of 14 miles of flying at ridge speeds, and most certainly reduced my speed for the day. 

Winner's Analysis: 

Let's compare and contrast what Noah Reiter did (HH) and what I did: 

Noah was last to launch.  His copilot was one of the tow pilots for the day.  I think this worked to his advantage. I started at 13:31, and he didn't start until 13:49. Noah was still in his first thermal climb while I was starting the task.  Why did I start so early?  I don't know.  I'll have to figure out why I have a tendency to start as soon as possible.  It could be because I don't really understand the strategy of the start games that the experienced pilots play. 

When Noah was starting the task, I was circling with Karl to make the jump across the Susquehanna river. 

Noah crossed the start line in the center of the start line.  I started on the southern end of it.  I don't think that made much of a difference.  Noah started lower across the start line than I did. Noah got to Shade Mountain at about the same height and position that I did. 

So far: Noah's track isn't that much better than mine. 

Before jumping across the Susquehanna river, I climbed to 3600 feet MSL. That thermal climb took about 7 minutes. Noah did a climb on Shade mountain about 2 miles to the west of where I did, and spent 5 minutes in thermal.  He left that thermal at about the same height I did. We both got across the river in the same amount of time, and showed up at about the same place. 

First Turn Area Observation

Noah made the right decision to go as far as he could into the first turn area. It's unclear why I turned early. When I turned it was 67 miles into the task.  When Noah turned, it was 72.7 miles. It took him 6 minutes and 23 seconds to go that extra distance.  During that difference in our ground tracks, he had an average of 107.15 mph. 

Noah "HH" (cyan) turned later than I did (red), and made great speed while doing so

Second Crossing of the Susquehanna

It took me 17 minutes to find a suitable enough thermal to get across the river. I made 3 thermal attempts.  Noah did the crossing in 14 minutes, and also made 3 thermal attempts. 

Second Turn Area

As mentioned before, I turned before everybody on that ridge.  This was no exception with Noah's flying.  He turned 4.6 miles later than I did.  The extra time on his trip was almost 6 minutes.  The average velocity while he did that extra 9.2 miles was 92.7 mph. 

Noah "HH" turned later into the turn area than I did. 

Third Turn Area

This is beginning to be a theme.  I turn just a few minutes after getting into the third turn area.  This is along the same section of Shade Mountain that I had been on earlier in the day.  I don't know why I turned when I did, or why I decided to turn at that point. I made my turn at 15:30:23, and my distance task so far was 162.7 miles in total. When Noah did his turn, it was another 13.1 miles of distance, covered in 9 minutes and 52 seconds. 

Shade-Jacks Transition

Noah and I both circled in thermals at about the same point on Shade Mountain.  He did a much better job of circling, left earlier, arrived at the top of Jacks Mountain. He started his upwind journey to Jacks Mountain at 3070 feet, where I started at 3260'.  He arrived at Jacks mountain at 2034', where I arrived at 2385'. It took Noah only 7 minutes to do the transition. It took me 9 minutes. The numbers aren't that terribly different, but he certainly did a better transition here than I did. 


Noah did a slightly better transition from Shade
Mountain to Jacks Mountain than I did

Mill Creek Turn Area (Fourth Turn Area)

In the final turn area, Noah covered another 8.3 miles, and it took him almost 6 extra minutes of time to do this. In the meantime, I came in for a landing well under the minimum time. On my return leg, there wasn't much point in pushing the return trip.  I was going to suffer a time penalty and it was going to hurt my score either way.  Noah had managed to fly the course without a minimum time penalty, and he was the only one in our class to do so. 

Piet's Lessons Learned from Day 2

  • When doing a ridge task, do everything you can to go as far into each turn area as you can safely accomplish.  Those extra miles make all the difference, and you'll be less likely to come in under the minimum time. 
  • If there are four turn areas, and you turn earlier than everybody else in those four turn areas, don't be surprised when you come in dead last. 
  • At least I didn't land out.  My low altitude scratching skills aren't that bad.  It took me about the same amount of time to transition across the Susquehanna river as everybody else. 
  • I should have a better understanding of how much altitude I need to get across the Shade-Jacks transition, without having to spend extra time tanking up on altitude. 
  • Leaving first out of the starting gate on a ridge day is stupid.  Especially for somebody of my skill level. Let one of the more seasoned veterans go first. On the ridge, they're not going to pull that much further away from me. 
  • Figure out why the HAWK variometer is showing wildly different wind directions while doing ridge flying. There were times in the flight when the flight computer showed 180 degrees out of phase with what the winds were really showing. (I have disabled the compass on my flight computer, and will do another software update before flying on the ridge again)
  • I judged the correct mountains for this task.  Other guys went to the Tuscarora.  They didn't place that well.  I took the right course, just didn't go far enough into each turn area. 
  • I could probably fly a few miles per hour faster along the ridge than Noah did.  I had water in the wings, and Noah didn't. I think I can get lower on the ridge and make better speed. 

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