Glassy Water Approach and Landing (ASES, AMES)

Maintain the manufacturer's published approach airspeed, or in its absence not more than 1.3 VSO, ±5 knots (CA.IV.J.S6) — tightened from +10/−5 at private.

Note there is no touchdown distance box on this Task. The graded outcome is instead: contact the water in a proper pitch attitude and slow to idle taxi speed (CA.IV.J.S8), with directional control maintained throughout (CA.IV.J.S9).

Because the hazard is perceptual, not meteorological. Glassy water means no wind, no crosswind, no weathervaning, no chop — which produces a false sense of safety. But the lack of surface features makes accurate depth perception very difficult, even for experienced seaplane pilots (FAA-H-8083-23 ch. 6). Without knowing your height, you flare too high or too late: flare too high and stall, and the seaplane pitches down, very likely striking the water with the float bows and flipping over; flare too late or not at all, and it flies into the water at speed, landing on the float bows, driving them under and flipping over.

The smooth, reflecting surface reproduces clouds and shore features in stunning detail and full color, which is confusing in itself. Worse, when the water is crystal clear and glassy the surface itself is invisible, and pilots may inadvertently judge height using the bottom of the lake as a reference instead of the water surface (FAA-H-8083-23 ch. 6).

Land near the shoreline, using shore features to gauge altitude, after inspecting from a safe altitude to confirm the water there is deep enough and free of obstructions — or make the final approach over land, crossing the shoreline at the lowest possible safe altitude so you keep a reliable height reference to within a few feet of the water (FAA-H-8083-23 ch. 6).

When adequate visual references are not available, you fly a stable descent in the landing attitude and let the airplane arrive (FAA-H-8083-23 ch. 6):

1. Always perform glassy water landings with power. Recognize the need early enough to set up the proper final approach.
2. Fly a normal approach, but prepare as though intending to land at an altitude well above the surface — for example 200 feet above it where the altimeter setting is uncertain and cues are few.
3. Complete the landing checklist and extend flaps as the manufacturer recommends.
4. At approximately 200 feet above the surface, raise the nose to the attitude normally used for touchdown and adjust power for a constant descent rate of no more than 150 feet per minute at an airspeed approximately 10 knots above stall speed.
5. Maintain that attitude, airspeed, and rate of descent until the seaplane contacts the water. Do not flare.

Almost nothing — deliberately. Once the landing attitude and power setting are established, the airspeed and descent rate should remain the same without further adjustment, and you closely monitor the instruments to maintain the stable glide. Change power only if the airspeed or rate of descent deviates from the desired values (FAA-H-8083-23 ch. 6). The temptation to "help" it near the surface is the accident.

Because you may not be on the water. Close the throttle only after the seaplane is firmly on the water — accidents have resulted from cutting power suddenly after the initial touchdown when a skip had taken place and the seaplane was 10 to 15 feet in the air, resulting in a stall and substantial damage (FAA-H-8083-23 ch. 6).

Verify with three senses before you touch the throttle: you see a slight nose-down pitch at touchdown and perhaps spray thrown to the sides, you hear water against the floats, and you feel the deceleration force.

Extra drag. With less turbulence and fewer air bubbles between the float bottoms and the water, the contact is continuous rather than intermittent and the drag forces are higher, so a smooth touchdown decelerates faster than expected and the sudden drag pulls the nose down. Anticipate it and maintain the planing attitude with appropriate back pressure — controlled that way it presents no problem (FAA-H-8083-23 ch. 6). After it settles into a displacement taxi, complete the after-landing checklist and lower the water rudders.

Yes, conditionally. An accurately set altimeter may allow you to set up for touchdown at an altitude somewhat closer to the surface — and if you can be certain the landing configuration and 150 fpm descent will be established well above the water, starting the final glide nearer the surface shortens the descent time and the overall landing length (FAA-H-8083-23 ch. 6).

The trade is explicit and it is the reason 200 feet is the default: lower start means less margin for establishing the stable condition, and the whole technique depends on the condition being stable before the surface arrives.

Distance. The technique usually produces a safe, comfortable landing, but the long, shallow glide consumes considerable landing distance — so be certain there is sufficient room for the glide, the touchdown, and the water run (FAA-H-8083-23 ch. 6).

That interacts directly with the confined-area problem in Task IV.H: a glassy day in a terrain-bounded lake gives you the longest landing profile you fly and the hardest takeoff, at the same time.

The energy state has to be correct from 200 feet down, because there is no terminal correction to fix it. Normally the round out is where you convert the last of your kinetic energy into a reduced descent rate; here you delete that step. The airplane arrives at the surface with exactly the vertical energy you set with power (150 fpm) and the horizontal energy you set with attitude (about 10 knots above stall). That is why the standard grades attitude and taxi speed rather than a landing spot: on this Task, the approach is the landing.

Gear up, for water. The ACS carries gear position as a distinct risk element on this Task. A stabilized 150-fpm arrival with the wheels down puts you inverted, and the same absence of surface cues that makes the technique necessary also removes any chance of catching the mistake visually on short final.