Domain: Engineering — Aerospace Engineering
Target concept: Paper gliders released from the same altitude with nose-up and nose-down trim.

Video generation prompt: In a large indoor hall, two identically constructed paper gliders were released side by side from the same height, without any thrust, and descended toward the ground, one adjusted with a nose-up attitude and the other with a nose-down attitude.

Evaluation guide:
(i) Target concept: Angle-of-attack-dependent lift generation in unpowered gliding flight.
Minimum mechanism: Paper gliders must behave as lightweight, low-Reynolds-number lifting bodies where pitch attitude directly controls effective angle of attack; airflow must separate predictably such that increased nose-up attitude yields net upward aerodynamic force component (lift) sufficient to oppose gravity more effectively than nose-down configuration.
(ii)Storyline: Frame 0–1: Static side-by-side hold at identical height, clear visibility of nose-up/nose-down trim contrast. Frame 2–3: Simultaneous release from rest (no limb acceleration, no forward velocity). Frame 4–7: Continuous descent with divergent trajectories: nose-up glider maintains elevated pitch and shallow descent slope; nose-down glider maintains depressed pitch and steep descent slope. Frame 8–9: Both gliders contact ground: nose-up glider lands farther from release point; nose-down glider lands closer. Perspective: Fixed frontal or 30° oblique view, full-body visibility of both gliders and floor contact zone throughout; no occlusion; hall-scale context (ceiling, walls, floor markings) continuously present.

Manual:
Experimental Procedure
1. In a large indoor hall, hold two identical paper gliders side-by-side at the same height.
2. Adjust one glider to nose-up trim (front edge elevated), the other to nose-down trim (front edge depressed).
3. Release both gliders simultaneously from rest—no thrust, no push.
Observation of Experimental Phenomena
The nose-up glider descends slower and travels farther horizontally; the nose-down glider descends faster and lands sooner with less horizontal travel.
Summary of Experimental Principles
Nose-up trim increases angle of attack → higher lift and drag → reduced sink rate, longer glide. Nose-down trim decreases angle of attack → lower lift, higher weight dominance → steeper, faster descent.

Prompt Grounding rubric:
level_1: No paper gliders visible; or only one glider present; or the two gliders are not released from the same height; or they are not released side by side; or the release includes any thrust (throwing, flicking, a forearm swing); or the setting is outdoors, sunlit, or otherwise not the large indoor hall described.
level_2: Two paper gliders are present and released side by side, but at visibly different heights; or one glider shows a clear nose-up trim while the other fails to show a matching nose-down trim (e.g., both look neutral, or both tilt the same way); or the release comes from a hand still moving rather than a clear static hold at identical elevation.
level_3: Two identically shaped paper gliders are released side by side from the same visible height inside a large indoor hall; both leave the hand with zero forward push (no arm swing, no flick); one glider's nose is visibly raised relative to its tail (nose-up trim) and the other's nose is visibly lowered relative to its tail (nose-down trim); both begin falling from a simultaneous, static release.
level_4: Everything described at the 3-point level is present, and in addition both gliders stay fully visible for the entire descent with no hand, pillar, or hall fixture blocking either one; the nose-up vs. nose-down trim contrast stays legible in every frame from release to floor contact; and nothing extra (fingers, string, launch rig) intrudes on the falling path after release.
level_5: Everything described at the 4-point level is present, and in addition the two gliders keep a steady side-by-side lateral gap all the way to the floor (neither drifts to fully overlap or hide behind the other); the hall's ceiling, side walls, and floor markings stay within frame throughout so the indoor-hall setting is never in doubt; and the camera holds one fixed frontal or roughly 30° oblique framing without panning, zooming, or cutting to a different angle.

Scientific and Causal Correctness rubric:
level_1: No visible difference in descent speed or path between the two gliders; or both fall in a visually identical way; or the nose-up glider reaches the floor before the nose-down glider; or either glider is shown climbing, hovering in place, or accelerating upward after release, all of which contradict how nose-up trim raises lift relative to nose-down trim.
level_2: Both gliders descend, but no consistent difference in glide behavior shows up between them; or a difference appears (e.g., one veers left, the other right) that has nothing to do with trim; or the nose-up glider lands clearly sooner than the nose-down glider, the opposite of what a higher angle of attack should produce.
level_3: Both gliders fall toward the floor, but the nose-up glider visibly stays airborne longer and/or travels farther across the hall before landing, while the nose-down glider reaches the floor sooner and/or covers less horizontal distance; this gap in airtime and travel distance tracks consistently with each glider's trim from release to landing.
level_4: Everything described at the 3-point level holds, and in addition the nose-up glider keeps its nose visibly raised for most of the descent while the nose-down glider keeps its nose visibly lowered for most of the descent; neither glider's pitch flips to the opposite trim partway down.
level_5: Everything described at the 4-point level holds, and in addition the nose-up glider settles into a gentle, sustained glide with little wobble, while the nose-down glider holds a steeper, more direct fall with little lift-driven wandering; at no point does the nose-up glider plunge like a dropped weight, nor does the nose-down glider unexpectedly balloon upward.

Spatiotemporal Consistency rubric:
level_1: Either glider drops out of the shot and pops back in somewhere else, or appears in the frame with no visible release moment before it; motion blur is heavy enough that you can't tell the two gliders apart or judge their position; the hall's lighting cuts out or swaps abruptly (e.g., the overhead lights or window glow present in the opening shot are suddenly gone or replaced); or a glider's wing detaches then snaps back into place, or its paper body folds and unfolds in a way no real paper glider could.
level_2: A glider's position skips forward by roughly its own length between two frames with no visible motion in between; a hall pillar or fixture briefly hides a glider and it resumes on a different path once visible again; a glider's edge flickers on and off repeatedly; the shadow a glider casts on the floor swings to a new direction even though nothing shows the hall's lighting moving; or there is a visible seam where two separate shots have been stitched together.
level_3: Both gliders stay in view along one continuous flight path from release to floor contact, with no skips forward, no dropping out of frame, and no sudden reappearance elsewhere; the shadows they cast on the floor keep pointing the same way and stay sized in proportion to each glider's height above the ground, matching the hall's fixed overhead lighting; the ceiling and side walls visible in the background stay lit the same way the whole time; neither glider's wings or body bend, tear, or reform in a way that breaks its paper-glider shape; both fall the way gravity and air resistance would carry them, never floating in place or snapping between positions.
level_4: Everything described at the 3-point level holds, and in addition each glider's motion looks continuously smooth frame to frame, with no visible skipping, juddering, or stop-and-start stutter; the camera framing itself never drifts, pans, or tilts; and there is no jump cut, repeated frame, or moment where the action appears to run backward.
level_5: Everything described at the 4-point level holds, and in addition both gliders keep crisp, recognizable outlines all the way down rather than smearing into a blur; the hall's background (walls, ceiling, floor markings) stays aligned frame to frame with no shifting or misregistration; neither glider leaves a trailing double image or ghost copy of itself; and each glider's fall shows a gradual, natural build in speed rather than an instant jump in velocity.