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Hop #11

Despite scheduling my flight for later in the day today, the winds still hadn't died down when I got to the airport. When I strolled out to start preflight, the winds were 10-15 knots - directly across the runway. Sigh. So no way I was going to solo today. However, lemons->lemonade - I needed to work on crosswind takeoffs and landings anyway. My instructor wandered out as I was finishing the preflight. "What've we got?"

"5 gallons right, 7 gallons left, 6 quarts of oil, all correct."

"So that gives us how long?"

Thought for a second. "Uh, at 9 gph that means an hour and twenty minutes, with a 45-minute reserve...yeah, we need to gas it."

"Yep. And, handy - look, there's the tow cart." It was true; one of the airport employees was towing a Piper Warrior past our nose, returning from the fueling stand. My CFI jogged after him, and he parked the Warrior and came back. They hooked 12732's nosewheel up with a tow bar, and he pulled the airplane over towards the pumps. My CFI and I stood on the apron for a few seconds, just looking around - windsock, trees, sun, clouds - and then walked after him. I unrolled the grounding strap and grounded the airplane on the exhaust pipe, then unrolled the fuel hose and hauld the ladder out with me. Climbing up to the right wing, I remembered this time to stick my middle finger down into the tank as I filled it, wiggling it to determine when the gas was nearing the top.

Unfortunately for me, the fuel was right around body temperature - the airplane was hot from sitting in the sun, and the fuel pump was at ambient at around 90 F, so just as I was saying "Hey, that feels like..." a geyser of avgas shot out of the tank.

Sigh.

Next tank I climbed all the way up on the ladder, stuck my Cool Pilot Sunglasses(tm) up on my forehead and squinted into the darkness of the tank; this time, I could just barely see when the sloshing started near the top, and I decided discretion was the better part of valor and declined to top the tank off.

Hm, maybe *this* is why the right tank on 12732 is always slightly fuller than the left...

Anyway, rolled the hoses and grounding strap, got settled, fired up the mill and looked around. "Which runway should I use?"

"Well, it's right down the middle - " at that moment the radio crackled.

"Northampton traffic, Piper zero two Victor is inbound north of the field, entering a left crosswind for runway one four Northampton."

"Okay, I guess I'll use one four then." Got a shrug and a nod, taxied around and down to the departure end of one four.

"Traffic on the ground at Northampton, this is Piper zero two Victor, I can take a long downwind if you'd like to go."

*click* "Zero two Victor, Skyhawk 12732 - negative, we have to do a runup anyway, take your time."

"Zero two Victor, thank you."

Did the runup - power to 1700, check ammeter? check; oil pressure? check; fuel? check; suction? check, then left magneto? 50 RPM drop, check; right magneto? 75 RPM drop, check; carb heat? 100 RPM drop, check, pull the power back to 1000. Set the transponder to ALT/1200, set the gyrocompass and altimeter. While I was busy with this, zero two Victor had floated past us and was taxiing back for the last turnoff. "Northampton traffic, zero two Victor is clear of the active."

Declared departure and taxied out to the centerline. My CFI reached over. "Okay, crosswind from the left, so...correct, full left aileron, roll that out as you get speed and have it fully out for climbout."

Brief digression for crosswind ops. Normally, you pick the end of the runway that has you taking off and landing with your nose into the wind for additional lift and for shorter rolls. However, sometimes (as today) the damn wind is not cooperating, and is directly across your available runway. Larger airports have multiple runways, and most of them have at least one 'cross' - runways that are perpendicular to each other for this very reason. That gives you four directions and four chances at having a runway aligned properly for the wind - and means your maximum crosswind component will be 45 degrees. 7B2, however, like most small fields, has one runway - and if the wind is across it, well, tough noogies.

Crosswinds have to be compensated for on takeoff and landing. Let's go with takeoff, because that's what I'm about to do. In this case, you might think that so long as the wheels of the airplane are on the ground, it can be ignored - but not so. Especially with a high wing airplane like a Skyhawk, a crosswind can get 'underneath' the upwind wing. If it does that, it can lift that wing high, with all that wing surface to push on. At best, that will mean you'll be lucky to avoid ground looping the airplane as one half of your main landing gear leaves the ground. At worst, it can (and has) ended up throwing the airplane entirely over on its side. This is not likely in a 15-kt wind at rest or taxi - but remember, just before takeoff, the 'apparent weight' of the airplane is nearly zero as lift on the wings develops, so all the wind really has to do is tip over a neutrally balanced aircraft - and that's completely not keeping the shiny side up.

So before you start your takeoff roll, you turn your yoke completely into the wind. This causes the upwind wing's aileron to rise (and the downwind one to lower), developing a downforce on the upwind wing. Thus, the upwind wing stays low, and any wind pressure just pushes you harder onto your gear. However, as you get close to liftoff, you want to make sure that correction is neutralized so that you don't lift off the ground and immediately start rotating upwind, possibly tapping your upwind gear or maybe even scraping a wingtip. So, as your aircraft picks up speed and the ailerons develop enough force to allow you to compensate with less and less deflection, you start 'rolling the correction out' - and by the time the wheels lift, you should have the yoke centered again.

Now, of course, the airplane will immediately begin to drift downwind, although without rolling. This can be bad. So as soon as you're off the ground, you point the nose of the airplane slightly upwind, enough so that your ground track follows straight out from the runway - correcting with rudder rather than aileron.

Voilà, a crosswind takeoff.

So I did that.

On climbout, turned east/crosswind a bit early as one four's flight path takes you towards the ridgeline hills southeast of the Connecticut River. As I came around to a downwind, my CFI asked "So what will the wind be doing?"

"It's going to blow me in towards the runway, so I should stay a bit wide and be ready for an abbreviated base leg."

Did that, but as I came around for my first landing, I said "I think I'm high." Turned final, looked at the runway - yeah.

As we floated over the threshold, my CFI said "Where are we going to touch down?"

Looked. "Too far down." Slid the throttle back in. *click* "Northampton traffic, Skyhawk 12732 is going around for one four Northampton." Carb heat out, flaps up, steadied back on climbout. "I was high. How'd I end up high?"

"You knew you were going to have a short base due to wind, but you didn't take the power out all the way early enough. Even then, you could have added more flaps, but you only had twenty degrees of flaps on coming into final and you still had 90 mph, not 70, to deal with."

"Yeah. Okay, round two!" Came around the pattern again; this time I left the nose five or ten degrees east of the downwind vector to compensate for wind, and when I came into the base leg, I was noticeably further out from the runway. Put in the second ten degrees of flaps on early base, and as I turned final, dropped them to thirty degrees; ended up looking at a red-over-white VASI at 70 mph with ten degrees of flaps in reserve. Pulled power and flew it down-

Digression. Crosswind landings. These aren't quite 'takeoffs in reverse.' The problem with a crosswind landing is that while you're trying to line up your nose and landing gear with the runway centerline, the wind is busily pushing you sideways as you are on final approach. Spending the whole time making corrections isn't the answer. The best option is to offset the nose to compensate for the wind as you come onto final, and adjust that offset (or 'crab') as you get closer to the runway.

If done properly, you'll end up just over the runway numbers with your landing gear pointed somewhere left or right of centerline. This is okay; the trick is to wait until the last moment, and then use the rudder to align the nose with the runway right before you touch. This means the airplane won't have a chance to drift, and using the rudder means your wings will stay level to avoid the risk of being blown over and sideways. Once the landing gear is down (or just before), then you roll in the upwind aileron just like you were using on takeoff; since the wing no longer has the lift to pull the airplane off the ground, it can't rotate far but the upwind wing will dip just enough to prevent it from ballooning.

In really high wind, of course, crosswind landings can get just crazy-looking. Especially on big airliners. YouTube has some fun videos of them. You can see that airliners often have landing gear which is steerable (even the main gear) and that in many cases, they will maintain the crab angle all the way until their main gear touches down, and then use the gear to 'steer' themselves straight! You will, in some cases, be able to see them touch their 'upwind' gear first as they maintain the aileron correction.

Of course, my landings were nowhere near that cool-looking, and in wind that was nowhere near that strong. Just enough to require the compensation, and just enough to make you feel like a Pilot(tm) on final approach, with the nose not pointed at the runway, looking out the windscreen slightly sideways at the runway and waiting for that last moment to tap the rudder and align the nose, waiting until enough speed has bled off that you don't end up floating long and thus having time to slide sideways.

Did six landings today. Got verbal props for four of them, including a couple I thought were a bit squirrelly but was told that nope, given the wind gusts, they were completely sweet. In all six, had minimal wheel squeak. A couple went a bit long, but as I got used to one four's approach (most of my ops have been on three two, so I wasn't used to the landmarks approaching one four) my speed and height got closer to the mark, and by the time we switched back to three two as the wind died for the day, I was coming down able to make the second turnoff.

Hoo yah.