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 had debunked this flying myth in 2012, and have recently confirmed that Bernoulli’s principle cannot explain everything in wing lift. 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 avaient démonté ce mythe du vol en 2012 et viennent de confirmer que le principe de de Bernoulli ne peut pas tout expliquer dans la portance de l’aile. 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?



Czech Pilot Wins First Race

The 2017 opener has been full of surprises. A victory of Mathias Dolderer was expected in Abu Dhabi today but the Czech Martin Sonka and his Zivko Edge 540 V3 had the last word thanks to his first victory in this competition. The German champion finished fourth. Two French pilots – Nicolas Ivanoff and François Le Vot – reached the Final 8 but failed to go through. Master Class results: Sonka (CZE) 15 points, Velarde (ESP) 12 pts, McLeod (CAN) 9 pts, Dolderer (GER) 7 pts, Ivanoff (FRA) 6 pts, Goulian (USA) 5 pts, Bolton (CHI) 4 pts, Le Vot (FRA) 3 pts, Brageot (FRA) 2 pts, Hall (AUS) 1 pt. The next race is to be hold in San Diego on April 15 & 16.



Have you ever wondered how many Londonian airports have been built since the 1900s? Here is one of the best videos I have seen about this topic. It is one of a series produced by the comedian Jay Foreman. Thanks to this great source of information, you can have the answer as well as some fun.

Another interesting video tells us the train options to connect the six London airports to the City of London:

As you can see, it may cost an arm and a leg to travel to London. However, London airport system is the busiest one in the world. It demands a lot of concentration from its air traffic controllers as shown in this previous post:



He took off that day. It was 115 years ago, two years before the Wrights. Gustav Weisskopf had changed his name into Gustave Whitehead before building his aeroplane whose name was the « Condor », or number 21. Gustave was a German immigrant from Leutershausen in Bavaria, where a splendid museum commemorates the feats of the brilliant inventor.

Two replicas of his plane #21 flew in 1986 in the U.S.A., and in 1997 in Germany. Several books have been written about Gustave Whitehead so far. Susan O’Dwyer Brinchman published the latest one last year. Her searching follows her father’s, Major William J. O’Dwyer, a retired U.S. Air Force Reserve officer who had found early Whitehead’s photos in an attic, in 1963, and researched Whitehead for the next 45 years, interviewing many witnesses. Susan worked with him during the later decades and recently, has found even more. She explains why Whitehead must have been the first in the world to perform a steerable, propelled without catapult, heavier-than-air flight. She shares an extensive FAQ and lots of resources on her website here:  which are quite compelling. You can order her book Gustave Whitehead: First in Flight on Amazon or get a signed one by clicking on the cover here below:

Book cover First in Flight on Gustave Whietehead by Susan O'Dwyer BrinchmanBook cover story of Gustave Whitehead First in Flight aviation history Connecticut



Here is a remarkable video for training purpose. It is not easy to understand how air traffic is managed at Heathrow airport but this video helps a lot to make out the stakes:
Voici une vidéo remarquable à but pédagogique. Il n’est pas facile de comprendre comment la circulation aérienne est gérée à l’aéroport de Heathrow mais cette vidéo est d’une grande aide pour comprendre les enjeux:

Note that there are four stacks in the vicinity of London. The word « stack » means « holding pattern » here. However, stack can mean another thing in aeronautical and general English. For instance:

Notez qu’il y a quatre « stacks » aux environs de Londres. Le mot « stack » signifie ici « circuit d’attente ». Cependant, stack peut vouloir dire autre chose en anglais aéronautique et général. Par exemple:

  • Stack of folders = Pile de dossiers
  • Smokestack = Cheminée d’usine
  • Hay stack = Botte de foin, meule de foin
  • Radio stack = Equipement radio à bord de l’avion (radio com, radio nav, transponder)
  • Wood stack = Tas de bois
  • Stack up / Stack down = Espacement décalé vers le haut ou vers le bas entre des avions de chasse ou d’acrobaties aérienne
  • Vent stack = Colonne de ventilation
  • To stack = Empiler, entasser
  • Stack = Circuit d’attente dans l’espace aérien londonien pour les avions à destination d’Heathrow

Note that easterly operations match westerly winds, and westerly operations match easterly winds.

Notez que les opérations d’est correspondent aux vents d’ouest, et que les opérations d’ouest correspondent aux vents d’est.