October 2001

CYSN with the Snowbirds - Fall 2001

Flight Notes:

With the approach of fall here in the Great Lakes area it is common to see strong gusty surface winds. Since the KR manual is a little light on flight information it falls upon the pilot/builder to determine most flight parameters including x-wind limits.

I have flown the Gadget on days with recorded gusts as high as 30 Kts at 30 degrees to the runway. The good news is that the x-wind component (in this case 15 Kts) was within the aircraft's capability. The low wing and powerful rudder give the KR good x-wind landing capability in the hands of a practiced pilot (and even I can manage OK).

The bad news is that when you have strong and gusty surface winds like this you are also going to have a good deal of mechanical turbulence in the lower levels. The KR is quite light (roughly 62% of a C150) with a low wing loading and does not penetrate well. The pilot can only react to the gyrations the aircraft is certain to go through in these conditions. I usually react with four letters in these situations - doesn't help much, but makes it sound like I'm doing something.

The final approach will likely be the most "interesting" phase of a flight. It will not be uncommon to have departures in roll of 45 deg and yaw of 20 - 30 deg (insert your favorite expletive here). Fortunately this mechanical turbulence usually will lessen in the final 150 feet and once in ground effect things improve even further.

My suggestions for dealing with these conditions are:

1) Avoid flight when wind gusts are recorded in excess of 25 Kts.

2) Avoid operations on runways with 15 Kts x-wind component or greater.

3) Increase approach speed to maintain safe margin above stall. (I have used 90 MPH in some cases). It seems the airspeed fluctuates more so in this aircraft than others I am familiar with.

4) If you have not stabilized the approach by 100 AGL go around and try again. Gusts are by nature transient. The next approach may encounter easier conditions.

5) If after the third try you are still unsuccessful consider your alternate (guess I should have planned for one). Some airports (runways) are better than others when it comes to approach turbulence. Remember that gusty winds often abate quickly in the late afternoon. If you have fuel to loiter, the closer you get to sundown the easier things may get.

6) Make sure you practice your x-wind technique. You should be able to consistently land the a/c on the upwind wheel and then slowly lower the downwind main to the runway while maintaining (or even increasing) your x-wind control inputs. By the end of your roll out you should have full upwind aileron deflection. This is not an aircraft which can be forced onto the runway and kept straight with nosewheel steering.

Forced Approaches:

In order to estimate gliding range the following test was performed.

The aircraft was climbed to 4500ASL stabilized in low cruise (120mph) on a heading of N. Power was then reduced to idle and the GPS odometer reading was noted. A glide speed of 70 - 75 mph was used (an estimate for best glide) and the odometer reading was then noted passing thru 3500ASL. The test was then repeated on a heading of S. The following results were obtained:

N S

Odometer Start: 3871.4 3880.4

Odometer End: 3873.1 3884.0

Distance traveled: 1.7 sm 3.6 sm

Average: 2.65 sm per thousand feet of altitude loss.

Average VSI indication through test was - 600 fpm. Based on a zero wind and average airspeed of 72.5 mph we can estimate a distance of 2.01 sm per thousand feet of altitude loss.

The values are reasonably consistent and compare favourably to a C172 which can be expected to yield 1.75 sm per thousand feet of altitude loss.

For flight planning purposes a 2 sm /1000' figure seems a good estimate.

Grass Runways:

The stock KR is not well suited to turf or gravel runways. The addition of fixed gear helps a great deal. Provided the field is smooth and well groomed it seems possible to operate on grass occasionally.

To test this I recently landed on a 2400' turf runway (32 at Tilsonburg ON). The landing was uneventful however the (stock) tailwheel functioned as an effective arrestor hook as soon as it came down. I decided to use the asphalt for departure since it appeared to have been some time since the field had been cut.

I plan to increase the size of the tailwheel next summer and will do some more testing after that time.