Y a-t-il un pilote dans l'avion? ou un physicien?
(pas trouvé de réponse par ailleurs, ...)
- Un vol New-York/Paris est plus court en durée de vol que dans l'autre sens. Le phénomène est bien expliqué un peu partout sur le net par le "jet stream".
Questions:
- ce phénomène se reproduit-il partout dans l'hémisphère nord, donc vols plus courts d'ouest en est?
- puisque les savants expliquent que le jetstream est dû à la force de Coriolis, ce phénomène est-il inversé dans l'hémisphère sud, donc vols plus courts d'est en ouest?
Pour l'hémisphère sud, je ne sais pas, mais côté Nord, oui, les trajets sont toujours plus longs d'est en ouest (il faut une heure de plus pour un Tokyo-Paris que pour un Paris-Tokyo).
La force de Coriolis "s'inverse" passé l'Equateur oui...
Les éviers siphonne l'eau dans l'autre sens... et tous les chiens dorment sur le dos!😏
(je plaisante pour les chiens.. quoique c'est un truc qui m'avait frappé dans l'Ocean Indien...)
La force de Coriolis "s'inverse" passé l'Equateur oui...
Les éviers siphonne l'eau dans l'autre sens... et tous les chiens dorment sur le dos!😏
(je plaisante pour les chiens.. quoique c'est un truc qui m'avait frappé dans l'Ocean Indien...)
Hello,
... La première fois que j'ai mis les pieds dans l'hemisphère sud, c'est ce que j'ai observé d'abord : comment s'écoulait l'eau du lavabo et des chiottes😏
En fait tout dépend de la forme des sanitaires, c'est elle qui définit le sens de rotation de l'écoulement de l'eau, il n'y a pas de sens unique selon les hémisphères pour des récipients aussi petits.
Cà n'est pas un "phénomène", c'est l'utilisation par des pilotes "intelligents"
de courants (assez localisés), d'ouest-en-est ...
Si on ne va pas "chercher" ces courants, alors on ne gagne pas de temps.
De plus, les courants en question ne sont pas immuables, il faut donc bien
"aller les chercher" 😉
Si vous avez compris tout ce que je viens de vous dire, c'est que j'ai dû faire une erreur quelque part. - Alan Greenspan
Science sans conscience n'est que ruine de l'âme - Rabelais
Bonjour,
La question n'est pas de savoir si les pilotes sont plus intelligents dans un sens ou dans l'autre😛, mais de savoir si les jet streams se produisent toujours dans le même sens et sont inversés entre les 2 hémisphères.
Il apparaîtrait notamment que ces courants ne sont justement pas "assez localisés", mais plutôt "largement rencontrés", et dépendant en effet de cette force de Coriolis.
Je continue mes recherches.😏
Encore ta lecture idéologique, cette fois ci d'une question de physique (bon allez, souris un peu, je plaisante!...)🙂
La question n'est pas de savoir si les pilotes sont plus intelligents
dans un sens ou dans l'autre
Ben, dans ce cas-là, la réponse est toujours NON !
Si un pilote est assez intelligent, il peut très bien EVITER les jets-streams
et donc ne pas être ralenti lorsqu'ils sont contraires ...
Cà ne veut pas dire qu'il peut toujours -sans changer d'altitude- s'abstenir de
les traverser (couper) brièvement ...
(en changeant d'altitude, on peut TOUJOURS s'en libérer)
Ailleurs, je vous avais donné une superbe référence de la Météo expliquant ce
phénomène (avec des petits dessins ...), pourquoi ne l'avez-vous pas consultée ?
🙂
Si vous avez compris tout ce que je viens de vous dire, c'est que j'ai dû faire une erreur quelque part. - Alan Greenspan
Science sans conscience n'est que ruine de l'âme - Rabelais
En lisant le texte, on se rend compte que "c'est pas simple", qu'il n'y a pas une
"autoroute" qui pousse ou qui freine, que "çà bouge tout çà" :
Other jets also exist. During the northern hemisphere summer, easterly jets can
form in tropical regions, typically in a region where dry air encounters more humid
air at high altitudes.
Low level jets also are typical of various regions such as the central United States
🙂
Si vous avez compris tout ce que je viens de vous dire, c'est que j'ai dû faire une erreur quelque part. - Alan Greenspan
Science sans conscience n'est que ruine de l'âme - Rabelais
Sauf... que les lavabos ont pourtant la même forme en France et dans l'île de la Reunion... et pourtant ils s'ecoulent dans l'autre sens...😇
Bonjour,
Il semblerait que dans un "système-lavabo", la force de Coriolis soit négligeable, et donc c'est plutôt la forme qui compte.
Le temps de vol est évidemment influencé par divers paramètres: nécessités commerciales, économies de carburant, etc...mais ce n'est exactement pas la question, d'ailleurs.
Il semblerait que dans un "système-lavabo", la force de Coriolis soit négligeable,
et donc c'est plutôt la forme qui compte.
Et quels sont les types d'avion qui ont des lavabos qui les font aller plus vite ?
😇
Si vous avez compris tout ce que je viens de vous dire, c'est que j'ai dû faire une erreur quelque part. - Alan Greenspan
Science sans conscience n'est que ruine de l'âme - Rabelais
Si vous avez compris tout ce que je viens de vous dire, c'est que j'ai dû faire une erreur quelque part. - Alan Greenspan
Science sans conscience n'est que ruine de l'âme - Rabelais
Lucky that we have a home/Our Home is Nha May Man/Passing rain and dry seasons/In a full-of-love atmosphere/Besides my new family/I have brothers and sisters/The sun shines over the skies/Let's stay here, with all of us,
héhéhé... je ne suis pas bien sûre que l'on parlait de tornade en parlant de F de Coriolis... mais de sens contraire du courant aerien ou non dans l'hemisphère Sud...
Ce qu'apparement ne marque pas ton shema ...
donc en effet lien entre jet stream et F de Coriolis ne serait pas si evident ...
Par contre je pense que par soucis de verité... on devrait chercher ses sources ailleurs que sur Wikipedia😇 ... ce qui ne veut pas dire que la personne qui a écrit l'article se trompe cependant... mais ce n'est pas exclu ...
Ben, voilà ce qu'en dit Encarta, c'es beaucoup moins détaillé, on ne mentionne
pas Coriolis (!) mais y raconte bien que les jet-streams vont d'ouest en est
(y compris dans l'hémisphère sud) :
jet-stream, vent très rapide (500 km/h), circulant d’ouest en est dans la tropopause,
frontière entre la troposphère et la stratosphère, à une altitude de l’ordre de 12 000 m.
Observé par les aviateurs américains le long des côtes japonaises à la fin de la Seconde
Guerre mondiale, le jet-stream, ou courant-jet, a été étudié par une équipe de météorologues
sous la direction de Carl Gustaf Rossby, qui le situe entre les zones équatoriales de basse
pression et les zones polaires de haute pression ; par ailleurs, ce courant-jet se localise
aux latitudes moyennes, entre 45° (en été) et 60° (en hiver, il se rapproche du cercle polaire),
dans les hémisphères Nord et Sud.
Le jet-stream désigne ainsi une zone de la circulation atmosphérique générale, définie,
pour une grande part, par le degré d’insolation et par la rotation de la Terre.
L’affrontement des vents polaires (orientés nord-est / sud-ouest dans l’hémisphère Sud
et sud-est / nord-ouest dans l’hémisphère Nord) avec les vents d’ouest, les westerlies,
(orientés sud-ouest / nord-est dans l’hémisphère Nord et nord-ouest / sud-est dans
l’hémisphère Sud) matérialisent les fronts polaires dans les deux hémisphères, le long desquels
s’établissent les jet-streams.
Ils se situent également à l’interface de deux cellules de convection atmosphérique majeures :
la cellule polaire de Hadley et la cellule intermédiaire de Ferrel.
Si vous avez compris tout ce que je viens de vous dire, c'est que j'ai dû faire une erreur quelque part. - Alan Greenspan
Science sans conscience n'est que ruine de l'âme - Rabelais
Et c'est bien dans la même direction (cas par cas) entre hémispère nord et sud ...
🙂
Si vous avez compris tout ce que je viens de vous dire, c'est que j'ai dû faire une erreur quelque part. - Alan Greenspan
Science sans conscience n'est que ruine de l'âme - Rabelais
J'ai acheté sur le site internet Bourse des Vols un billet Paris - Sihanoukville (Cambodge) en utilisant les comparateurs pendant de longues semaines. J'ai…
J'ai passé une commande pour 3 billets d'avion a 87€ soit 261€ et au final on me facture 373€ sur ma carte bancaire. En plus, et vu les forums, je ne suis pas…
Je viens d'acheter un billet j'ai lu les messages après mon achat:je sais c'est une mauvaise idee pour le moment j'ai reçu, la facture, mon ticket par mail…
Cette année, j'ai voyagée seule, j'avais choisi de prendre l'avion pour mon retour sur Strasbourg. malheureusement, on m'a volé mon appareil photo dans le bus…
Un membre singh de Voyageforum se permet d'utiliser une de mes photos sans mon accord et sans même lui attribuer son auteur d'origine Que faut-il en penser?…
Hello everyone! 🙂🙂,
A BIG thank you to all the travelers who sent us postcards this year—my students are becoming real geography whizzes!!!!!!!! I’m renewing my call for your kindness this year! We’re also working on food, so if your postcards can make our mouths water with local dishes, traditional meals, or typical recipes, that’d be amazing!!
Here’s a quick recap of the project:
I’m reaching out to all travelers and globetrotters on this forum. I’m a teacher in Creuse, working in a ULIS program (which welcomes children aged 6 to 12 with disabilities into a mainstream school). This year, I’m starting a school journal project that will involve the kids in many different topics. A big part of the journal will focus on opening up to the world, diversity, travel, countries, culture...
I’m launching a call to invite as many of you as possible to send us a little postcard (from France or anywhere in the world!) to take us on a journey and help us discover new places, countries, and horizons—much more fun and exciting than a regular geography textbook! One section of our journal could be called "We received mail from " and would be an opportunity to research that location and share what we learn with our readers (a super enriching activity in class).
The project starts in September 2025 but has no real end date, as this journal and world discovery initiative will span several school years (the kids stay in my ULIS program for multiple years). Postcards can be sent anytime—throughout the year, across seasons, even during holidays! (The kids will find them when they return.)
I hope this idea appeals to as many of you as possible and that you’ll spread the word to your fellow traveler friends. Make us dream, take us on a journey!!!
For those who’d like to write to us in a language other than French, no problem—quite the opposite!!
Thank you in advance for your participation(s)! Below is our address. Feel free to leave your own address on a corner of the postcard if you’d like us to write back! 😊
The ULIS program students
Bonnat Elementary School
12 rue Georges Sand
23220 BONNAT
Thank you, and see you soon, I hope! 😁
Julien
Many of us have noticed that bugs have been making it difficult to navigate the forum lately.
I’ll let Kate and Ticapi explain the issue:
I went to your profile to check out the Thailand travel journal, and when I clicked on it, it brought me back here again. All week, I’ve been dealing with bugs like this—it’s really discouraging from continuing on VF.🙁
I had the same thing happen, and multiple times. For me, it was Montagnard’s latest journal that kept coming up no matter which discussion I clicked on.
BOLIVIA: THE COUNTRY ON THE BRINK (What's Really Happening)
A dramatic saga is unfolding before our eyes in the Andes. Between suffocating blockades, clashes, an international airlift, and historic political decisions, Bolivia has just experienced 48 hours of rare intensity.
Here’s the full breakdown (economic, social, and political) of the last 48 hours:
For travelers and tourists: the article also includes an important note about the upcoming publication (starting tomorrow) of the precise status of roadblocks, route by route.
I’ll post the full update here on Voyage Forum!
Don’t miss this in-depth analysis. History is being written before our eyes! https://www.petitherge.com/bolivie-paralysie-et-ultimatum
I just discovered a great show on Arte.
It's called "7 en route": seven young European journalists travel around Europe in a fully converted bus, making reports on every city they visit. It's amazing! 🙂
Yesterday, for example, they were in Rome, Italy, and the reports included things like the world's smallest restaurant—a super romantic spot for two. There was also a report on the king of paparazzi in Italy.
They have to pick topics that let us discover the little quirks of each country. And at the end of each episode, we get to see the finished report.
It's such a great show, mixing journalism, travel, and discovery—basically, a must-watch!
It airs in the evening starting at 6:50 PM (I think), and it started this past Monday, July 14th.
If you watch it, let me know—we can chat about it!
I left my heart’s country eight days ago and returned to my adopted one—or was it the other way around? Scotland-Morvan, Morvan-Scotland, I’m not quite sure anymore.
After a quarter without dragging my slippers around here, even though I’d loudly declared I had no interest left in this site, here I am again!
My imagination never stays fallow for long. Just enough time for my inner land to rest. It gets overgrown with fresh nettles, the kind you can pick without getting stung. Then, it’s time to till the fragrant earth and let the story grow.
I hesitated over where to set this story.
Maybe the Highlands, maybe the Hebrides, maybe the Orkney Islands, maybe the Shetland Islands. All of Scotland is myth—easy to embroider.
But in the end, no. I’d almost be too afraid to bare my soul.
The story will take place at home. Simple, practical.
1)
This morning, I was up well before dawn, feeling a bit grumpy, but nothing a bowl of coffee won’t fix. I love my bowl, and no one dares take it. It’s porcelain, edged with intertwined blue flowers. On the bottom, it says "Revol." The factory has existed long before the Revolution. It was my great-grandmother’s bowl. She drank roasted barley from it during the war, then her Leroux chicory.
Last year, a little guy dropped it. My bowl broke into three pieces. A black anger vibrated deep inside me. The little boy was so upset, on the verge of tears. How could I scold him!
I picked up the three pieces and took Little Boy in my arms. His hair smelled of the light, sweet sweat of toddlers. A gentle hug that healed—his budding sorrow and my anger—everything vanished, and time carried on.
Today, my bowl is even prettier. Man fixed it using the traditional kintsugi technique, except he didn’t use gold powder or lacquer but superglue, and he delicately painted the cracks with woad blue. And my bowl is even more beautiful now.
I’m lingering, I can tell—it’s just that a story wraps itself in life, and life can’t be told in the snap of a finger. Life is long. Like in architecture, you start with a rough sketch, called a "sous-cul" (the initial pencil drawing), then you make a tracing, which is the work itself, the one you later carefully roll up in a wooden tube.
Life is like that: you erase, you start over, you use the nub of the pencil until it’s tiny, but you keep going—dreaming, loving.
"Living is a full-time occupation, a unique adventure. Always a surprise and a wonder, which sometimes turns into astonishment. And, from time to time, happiness."*
Alright, enough digressing—this introduction is definitely too long.
Tomorrow, I’ll get to the heart of the matter.
(I hate that expression; it feels like I’m cutting into someone’s skin.)
I’m Yann, a 28-year-old TikToker who loves traveling!
Since I’ve been to several destinations, I’d love to get a flag from each one as a sort of trophy. But from what I’ve seen online, a lot of sites sell them with what looks like really poor quality...
So I’m reaching out to you all to share a site you usually use—help me start my collection! :)
hi there
I’d love to get some opinions—I’ve never used Airbnb before.
They’re offering a key handover via lockbox.
Any tips or advice?
Is it reliable?
Best,
Hi there, I’m Laura, and I’m looking for a few people to answer some questions so I can understand your travel wishes and challenges. It won’t take long—I can chat here, by email, or by phone. Don’t worry, I’m not selling anything! 😊
On this forum, we talk a lot about trekking in the Himalayas, but I’d love to share another side of Nepal: its spiritual, cultural, and religious atmosphere, especially in Kathmandu.
Nepal, much like Tibet and Bhutan, is deeply connected to the Himalayas—the ultimate sacred mountain range. This small country exudes a calming vibe, shaped by a strong spiritual dimension. What I loved most was the unique sensory experience you get there. Walking around temples and tantric monasteries, a distinct scent fills the air—aromatic plants used for ritual fumigation. Locals mainly burn Himalayan juniper, cedar, sandalwood, and other local essences. This fragrant smoke is a way to purify the space and reach the deities, and you’re constantly enveloped in these aromas.
Another striking aspect is the sound. As soon as you step outside, you hear bells ringing in front of temples. People ring them three times before praying to announce their presence to the deities. Nepal is also the birthplace of singing bowls and sound meditation practices. In Kathmandu, you can easily find meditation sessions or "sound baths."
The spiritual dimension is everywhere: a Hindu sadhu practicing asceticism, a lama in deep red robes with his mala, turning a prayer wheel while murmuring "Om mani padme hum." Newar Buddhism, Tantrism, and Hinduism coexist harmoniously in daily life.
For those who love exploring a destination through its culture and spirituality, Nepal is an unforgettable place. What was your spiritual experience in Nepal like?
Hi,
I’m landing in Quebec and then heading to New Brunswick and Nova Scotia. I’d like to rent a pick-up. My question is: does this vehicle come with a cover and is it secure enough to store luggage in? I’ve heard two conflicting opinions. Thanks
I just installed the Maps.Me app on my phone. I only recently found out about this app. I’m traveling in 2 weeks and a few days, and I’m a bit stuck on how to use it.
I’m from the Montreal (Quebec) area, and I’d love to know if there’s a kind soul out there who could help me get started and use the app at least minimally.
If there are private lessons available, I’d be interested in those too.
Like many others, I’m overjoyed to hear that VoyageForum is reopening! I’ve been waiting hopefully for this, and it’s wonderful that it’s finally happening!
I just couldn’t bring myself to actively participate in other French-language travel forums—their format and way of doing things never appealed to me as much. I really hope that VF’s structure, categories, and interface won’t change too much despite the handover, because I’m very attached to them. Through thick and thin, the site has held strong—it’s amazing!
In a previous message, François mentioned that there were positions to fill ahead of the reopening, including moderators...
I’ve been eagerly waiting for this and hoping to send in my CV.
Now, after reading the latest message, it seems like the team is already fully formed. But are there still a few spots left to fill?
I’ve been a VF member for 20 years (since 2004). I’d love to contribute to this wonderful adventure as a moderator if VF would trust me with the role. If the team is open to reviewing it, I’m ready to send my CV. Could you let me know the next steps?
I’m planning a 3-week trip to Japan in May with Voyage Privé. The package includes a 5 GB eSIM, but my phone isn’t new enough to support it. VP told me I could buy a SIM card when I arrive at the airport.
Sure enough, I’ve seen online that this is possible with different providers.
I only need it for checking routes, looking up addresses, train schedules, etc.—basically using Google Maps, TripAdvisor, and similar apps. No heavy downloads or major internet use. All hotels should provide free Wi-Fi for that, right?
Has anyone got any tips for me on this? What have you tried, and how much did it cost?
Thanks for your help!
I’d like to know if you can buy reef-safe sunscreen sprays at 7-Eleven. If so, how much do they cost? We’re traveling with backpacks, so we’ll either buy 100ml here or in Thailand.
I wanted to share a really unpleasant experience from our last trip booked with Promoséjours and organized by FTI.
We booked an 8-day/7-night stay in Egypt, from June 8 to 15.
The flight initially scheduled was changed a week before departure to take off at 10 PM from Paris CDG.
In the end, it took off with a 1-hour delay and included an unmentioned stopover in Marsa Alam.
We landed in Hurghada at 4 AM and arrived at the hotel at 6 AM.
So, we spent our first night on the plane.
For the return trip, surprise—the flight was moved up. We left the hotel at 10:30 PM on Friday the 14th to take off at 2 AM and land at 7 AM at Paris CDG.
So, we spent our last night on the plane too.
After sending a complaint letter to Promoséjours / FTI, they replied that the first and last days can be dedicated to transport (which I already knew) and that no matter how many nights you book, you’re not guaranteed to spend them in the hotel—it could just as well be on the plane.
I’m really questioning this.
Isn’t there a law that protects customers in cases like this?
Because when I do the math, the first and part of the second day were spent on transport, same for the second-to-last and last day. And I paid for 7 nights for a stay that only lasted 5.
Anyway, I just want to say thanks to them—thanks to their two sleepless nights in transit, I’m coming back even more exhausted from a trip that was supposed to be restful!
I also want to warn anyone booking through this agency about visas for Egypt.
At booking, they told me the visa was included in the price, then they sent me an email saying I’d have to pay for it on-site at 25 €.
Once there, we were directed to a special line for FTI customers, and guess what? They charged us 30 €!
Basically, they’re great at making sure you *enjoy* your vacation—mostly by enjoying your wallet!
If anyone has dealt with this kind of situation and won their case, I’m all ears.
Hi there!
I’m heading to Thailand for two months.
So I thought I’d get a Thai SIM card to use Google Maps for getting around cities, mostly.
Here’s my question: will this SIM affect my apps? Or will they work the same as with my Orange SIM?
Is there any setup I need to do, or can I just pop in the Thai SIM?
I’d also like to switch back to my Orange SIM now and then while I’m in Thailand—on the same phone. Will I need to reset the phone, or will it reconnect without any issues?
Thanks in advance for your tips!
Best,
Huiclos
Hi, I’d like to know where we can buy beer or wine in Chefchaouen and around Merzouga. We’ll be doing a circuit and staying at the Parador Hotel in Chefchaouen and in a bivouac in Merzouga.
Thanks for any info you can share!
Hello everyone,
I’m reaching out to all travelers and globe-trotters on this forum. I’m a teacher in Creuse working in a ULIS program (which welcomes children aged 6 to 12 with disabilities into a mainstream school). This year, I’m launching a school journal project that will involve the kids in many different topics. A big part of this journal will focus on opening up to the world, embracing differences, travel, global cultures, and more.
I’m putting out a call to invite as many of you as possible to send us a postcard (from France or anywhere in the world)! The goal is to help us "travel" and discover new places, countries, and horizons in a way that’s much more fun and exciting than a geography textbook. One section of our journal could be called "We received a letter from ," where we’d research the location and share what we learn with our readers—a really enriching activity for the classroom.
The project starts in September 2025 but doesn’t have a strict end date, since this journal and world-discovery initiative will span several school years (the kids stay in the ULIS program for multiple years). Postcards can be sent anytime—throughout the year, across seasons, even during holidays! The kids will find them when they return.
I hope this idea appeals to as many of you as possible, and that you’ll spread the word to your fellow travelers. Help us dream and explore!
For those who’d like to write to us in a language other than French, no problem—quite the opposite!
Thank you in advance for your participation! Below is our address. If you’d like us to write back, feel free to leave your address on a corner of the postcard! 😊
ULIS program students
Bonnat Elementary School
12 rue Georges Sand
23220 BONNAT
Thank you, and I hope to hear from you soon! 😊
Julien
🙂
Hi there! I have to leave Ivato/Antananarivo on December 16th. I have a lot of ariary that I’d like to exchange for euros since I might not be coming back to Madagascar (after this 21st trip). I think the exchange office at Ivato also buys ariary back. If any of you have seen the rate for this buyback in advance, thanks a million!
Hi everyone,
I’m looking for a website that would let me plot my travel route in advance so I can print it out. The idea is to create a map with a little “me” on a bike that my parents can move along as I progress, since I’m planning to cycle all the way to Nepal.
If any of you have done something similar or know of a good tool, I’d love to hear your tips!
Thanks in advance! 😊
I'm looking to buy an ultra-lightweight 50/55L travel backpack with a suitcase or front opening.
Does anyone have any brand and/or model recommendations?
Thanks,
Emma
Hello. We’re a retired couple heading to Sri Lanka from January to March. After the November floods, I’d like to know if we can offer hands-on help to the locals, maybe pack some clothes or other items people might need in our luggage, and who we could give them to. Thanks for any info from those on the ground.
Be careful when sailing between Somalia and northern Madagascar.
It appears to be Somali pirates who have widened their search in the Mozambique Channel, far from their usual attack zone, since, to my knowledge, there are no Malagasy pirates.
Not sure if this is the right section, but just wanted to warn future travelers...
Where’s Cape Vidal?
It’s in iSimangaliso, an independent park in KZN Wildlife, stunning and just a stone’s throw from St Lucia (KwaZulu-Natal, Maputaland).
It’s the beach spot at the end of the Eastern Shores road. You can swim, fish... but watch out for waves, currents, and sharks...
There’s a really nice game drive where you can get out of your car at certain points, especially at Cape Vidal.
That’s where the camp with bungalows and campsites is.
The vervets and samango monkeys (endemic to the area, and the males are pretty big) can be a bit of a nuisance if you’re trying to braai...
They’re super persistent and not shy at all—don’t let them intimidate you, and stay alert because their speed at snatching food is impressive.
Anyway...
I’m reporting two recent attacks by these hyenas... who were *not* in a playful mood...
The first one happened at night—a hyena tried to bite a camper’s nose off in their tent... and succeeded.
The other night, a camper returning to their tent in the early hours was violently attacked by two hyenas... and they had a close call!
So, if you’re camping there, be careful...
Measures are being taken, but for now, it’s a bit risky.