WING LIFT THEORY SHAKEN – LA THÉORIE DE LA PORTANCE DE L’AILE ÉBRANLÉE

I had already written about that in my book UNE AUTRE HISTOIRE DE L’AVIATION, on pages 12; 13; 71; and others – Bernoulli’s principle does not explain everything. We know that aircraft fly. Strange as it may seem, Bernoulli’s principle has often been taught for decades as the explanation of the phenomenon.

Je l’avais déjà évoqué dans mon livre « Une autre histoire de l’aviation » aux pages 12, 13, 71, et d’autres: Le théorème de Bernoulli n’explique pas tout. Nous savons que les avions volent. Depuis des décennies, aussi bizarre que cela puisse paraître, on enseigne souvent le théorème de Bernoulli comme l’explication principale au phénomène.

This explanation would make sense if the air particles split at the leading edge of the wing and come together at the trailing edge. However, Cambridge researchers have recently debunked this flying myth. As you can see on the video above, the upper wing air stream travels much faster than the lower wing one. Last but not least, these air streams do not come together at the trailing edge since the upper wing air stream reaches the trailing edge well before the lower wing airflow. Isn’t this amazing?

Cette explication tiendrait si les particules d’air se séparaient au bord d’attaque de l’aile et se rejoignaient au bord de fuite. Cependant, des chercheurs de Cambridge ont démonté ce mythe du vol. Comme vous pouvez le voir sur la vidéo ci-dessus, le flux d’air en extrados voyage beaucoup plus vite que celui d’intrados. Enfin et surtout, ces flux d’air ne se rejoignent pas au bord de fuite puisque le flux d’air d’extrados atteint le bord de fuite bien avant le flux d’intrados. Étonnant, n’est-ce pas?

AD-150 HIGH-SPEED VTOL DRONE

Thanks to its HTAL (High Torque Aerial Lift) advanced tilt-duct propulsion system, the AD-150 Unmanned Aircraft System (UAS) has been designed to take off and land vertically (VTOL) as well as reach a speed of about 300 knots.

It is still being developed by American Dynamics Flight Systems. Its airframe is to be made up of carbon fiber and kevlar materials. It could be one of the most effective drones of its generation with its versatile payload configuration; GCS interfaces; and interoperable data links. Its Pratt and Whitney engines could be feed with Jet-A; JP-4; and JP-5 fuel.

VIDEO:

Mil V-12 or Mi-12 Homer – LARGEST HELICOPTER EVER

The Mil V-12 was the largest helicopter ever built (37-meter long!). It performed its first flight in 1968, and outperformed all the other helicopters in the world. Thanks to its twin rotor, it could lift up to 44 tons as early as 1969. It never entered service as this prodigious prototype remained at the project stage, and for uncleared reasons, its production was cancelled.

VIDEO:

HILARIOUS – Voice-activity elevator

Special thanks to LadyEleanorA who found out this great video.

VTOL Yakovlev Yak-38, Su-24, SU-25, SU-27, SU-34 and Mig-29 Specifications

Yak-38 Lift engines - Image © Tosaka/Wikipedia