Second Flight of Mark Langford's KR2S

N56ML's Second Flight...or how NOT to do your first flight in an experimental airplane!

created May 22, 2005

The first flight was made by Troy Petteway on Thursday, so Sunday was my turn. He'd already proven that the plane worked, so all I had to do was take care of the piloting part, right?

I guess I should start this story with my EAA Flight Advisor, Don Langford. Before Troy flew it, Don had asked if I'd checked my airspeed/VSI system, among a long list of other things. I told him I would, but also that I had a GPS, and he said "yeah, that sounds great in theory, but for landing it really doesn't work". The day before Troy flew it, I went through the static pitot system sealing everything against leaks, and the pitot system and altimeter held pressure for something like 15 minutes, full scale to zero, which certainly ought to work. But when he flew it, airspeed was erratic, along with the VSI, indicating a static system problem. Based on that, I checked it out, and it wouldn't hold pressure but a few seconds. We were also concerned that air deflecting off the tire might be influencing it, so I disconnected it in the cabin and left it open to cabin pressure. The thought was that it might not be accurate, but at least it shouldn't fluctuate. And indeed, the airspeed indicator worked fine up to the 60 mph takeoff speed, because I checked it on high speed taxis the day before I flew it.

So my plan was to takeoff, climb to 3000 feet or so, determine stall speed, and note it on the airspeed indicator. Whether it was accurate or not was unimportant, as long as I knew the indicated airspeed at which it stalled. All I had to do was multiply by 1.2 to get landing speed, 1.3 to get approach speed. Piece of cake, right?

The day before I flew it, I was buttoning up the plane when Don drove up and said "if I could arrange for you to fly a J-3 first thing in the morning, would you be interested?" I'd have been crazy to turn down that opportunity, so I agreed.


This morning, I drove to the airport through some pretty thick fog, but was pleased that the wind was completely calm. Right on time, Don taxiied up in a borrowed J-3. Although I'd never flown one before, I did three takeoffs and landings (with Don in back), and I did a decent job of it. That was one sweet flying airplane! Thanks, Don, for going the extra mile to help ensure that I was up to the flight.

By now, the fog had lifted somewhat and it was hazy, but I wasn't going very far anyway. So I really felt like I was ready for my flight, but knew the KR was going to be a whole different story. Just before my flight, I walked through the FBO and checked the winds...00 at 000. It doesn't get any better than that!


I did a few high speed taxi tests, just to get the feel of the KR again, which took a lot longer than I expected, because a whole bunch of planes came out of the woodwork and landed, took off, and generally made me sit around and wait. But I finally took off. Lift off was easy, but I knew getting down was going to be a little tougher. That plane climbs like crazy, and before I knew it, I was turning crosswind at pattern altitude. The first thing I noticed was my airspeed indicator was reading 70 mph, but the GPS said I was doing 117 mph. I guess it wasn't fixed after all! Also, the visibility was pretty bad, hazy, with low clouds. You'd have thought I'd have noticed that before I took off, wouldn't you? It didn't matter in the Cub, but I was planning on getting away from the airport to get familiar with the plane. And I couldn't climb any higher than 3000 feet without it getting really bumpy (the cloud bottoms), and could get only a few miles from the airport without losing sight of it. I did almost do a stall, and the GPS was reading 39 mph ground speed, but we know that ain't right. I had that thing pointed at heaven, and almost at idle, and it was flying incredibly slow, but it never broke either way, just mushed down a little. I guess that's a stall, but I won't swear to it. I later found out that a cross wind had come up while I was getting ready to fly and taxiing, and it was 8-9 mph direct crosswind on the ground. No telling what it was at 3000 feet, and I still don't know what my stall speed is.

The airspeed and VSI both were varying all over the place, but I never saw the airspeed indicator get over 80-90 mph. I think the static source being in the cockpit was just as bad as it being outside. I'd installed a NACA vent in the pilot's side the day before, and there's a huge difference in the amount of air (and therefore pressure) in the cabin depending on how much rudder I was giving it. Since the plane needed rudder trim anyway, I was always pushing on the left rudder, and still not doing a very good job of keeping the ball centered.

I'd planned to make two or three runs down the runway to feel the plane out, but it seemed like there were airplanes everywhere, and once I had to go around on final when I heard a guy on two mile final coming in behind me. I was there first, but I just didn't need the pressure. I finally got two runway excursions in, but they were both too fast, and it was gusty and bumpy. I was deliberately going fast enough to prevent a stall, but was too busy to look at the GPS to tell you exactly how fast I was going. I'm used to getting the speed right on, and letting the plane land itself. If you go screaming into the airport at 85 or 90, you're still flying, not mushing, and any movement of the stick is going to result in an immediate altitude change, and corresponding speed change. I was basically all over the place, and I started to wonder if I was going to be able to pull this off.

I noticed a group of people standing out in front of the FBO watching, and the whole gang in the MedFlight helicopter hangar was out front watching too. Apparently they were becoming concerned, or at least entertained. They told me later they were thinking about pulling the chopper out to let me know I'd be taken care of! Despite the 74 degree temp, I was really sweating.


I came around again, not really planning on landing this time either, but I was slower and under better control, so I decided to go for it. It seemed like I'd been up there forever (65 minutes), and I was ready to get it over with. I ended up a little high, so I probably lowered the nose a little, which made me even faster. I was going to wheel land it anyway, but apparently I did a "high speed" wheel landing.


I was doing OK as far as tracking the runway, but hit the ground pretty hard, bouncing back into the air. I felt like it was 20 feet, but they tell me it was closer to 6 or 7 feet. You can see from the photo that it was not a pretty landing. I instantly firewalled the throttle, thinking that would pull me out of the fire, but I did it so quick the engine died. I'd never seen it do that, but then I've never shoved it forward from idle to WOT in a millisecond either. I said to myself (and even keyed the mic at the time) "well, that'll work too!" I was ready for a beer, and I'll bet there were several folks on the ground who were ready for one too. I taxiied back feeling like an idiot, but quite happy to be back on the ground. Jeanie, Jim Hill, and Jim Ray walked up, flanked by the MedFlight gang. I was afraid Jeanie was going to tell me never to fly the thing again, but instead she said "don't worry, your next one will be better". What a woman! Well you know what they say: any landing you can walk away from is a good one, but if you can also reuse the plane, then it was a great one! So based on that, it was a great landing. As the MedFlight helicopter pilot put it, "takeoffs are optional, landings are mandatory". I know I was relieved to be back on the ground.

This flight would have been a whole lot easier if I'd just known my airspeed. I'm not going to get back in it until I have it calibrated, and I highly recommend that others do the same. I'd already made an extension for the pitot tube to get it out in front of the wheel and the wing, but wasn't smart enough to install it before I flew. I guess there's still a possiblity that it is too close to the prop stream, but it's right where the KR plans call for it, and my prop is no bigger than anybody else's (52"), so I really don't think that's it. That certainly wouldn't account for the low indications. And at full throttle I don't get any movement out of the airspeed indicator when on the ground. I think it's a static port thing, and I'll fix it before I fly it again. I also won't go until it's dead calm, crystal clear, and there's nobody at the airport but my ground support guy with the handheld. [later, I calibrated it and discovered it reads 53% of what it should read! See Airspeed Indicator calibration for details]

I'd hoped to show you the EIS plots, but I'm having trouble getting it to plot out properly. For some reason the EIS alarm kept warning me that my RPM was over 4500 rpm. It completely wigged out in the RPM department, but the bottom line is that my engine would only turn that prop up to about 3300 rpm when firewalled from 120 mph according to the Tiny Tach, given 5 seconds or so, so maybe I still have too much prop, but maybe not. But that flashing ultra bright LED between my eyes and the warning tone in my headset didn't help to keep the pilot any cooler. That "high rpm" trigger point is about to disappear. Max oil temp during the flight was 160F, and max head temp was about 340 on the hottest one. I did most of my flying at reduced throttle settings of around 2500 rpm, and saw 150 mph a time or two, so I feel like it'll have some decent speed when I start running it up higher. My first flight in it was not the time to find out how fast it would go though, especially in those conditions, and who's to say what was straight and level, since I had no horizon.

I never deployed the flaps, although I'm sure that would have helped a lot in getting slowed down on my landing, but I still wouldn't have known my speed. I want to work up to the flaps from a slow airspeed, making sure they can stand up to 80 mph, and then gradually up to 100 mph.

Well, you can bet I'm going to try a lot harder to stack the odds in my favor on the next flight, rather than AGAINST me. KNOWING my airspeed has got to make this a far easier task the next time around. Don't expect me to be in a rush to fly it again either. I paid my dues today, and I hope my membership will last a while.

And then there's life after near-death, as subsequent flights went far better!


Contact Mark Langford (if you must) at N56ML "at" hiwaay.net (replace the "at" with @)

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