|From: TimF||9/20/2018 9:01:17 PM|
|Can Planes Fly Through Thunderstorms and Hurricanes?|
by Alberto Riva
4 hours ago
Whenever a large storm front develops somewhere in the world, air travel gets a bit more complicated than usual. Air routes are closed, holding patterns are established, flights get delayed and some are unfortunately cancelled. Thunderstorms present a massive problem if they are standing between you are your destination, even if the area they affect is relatively small.
Hurricanes, however, are a beast of a whole other nature. Hurricanes are massive, spanning hundreds or thousands of miles and affecting flights on a regional scale. While a thunderstorm may develop and move through an area quickly, the effects of a hurricane linger for days. Airports directly affected by a hurricane will close for obvious reasons, often for days. Airport closures due to hunderstorms tend to be much shorter.
But what happens to all the flights that need to travel through a thunderstorm or a hurricane? First, airlines treat thunderstorms differently from hurricanes for flight-planning purposes.
The structure of a thunderstorm is drastically different from that of a hurricane. Thunderstorms and hurricanes are both convective in nature, but in different ways. Thunderstorms create massive cloud structures with tops that can reach over 60,000 feet, well above the cruising altitude of commercial airplanes, while hurricanes typically do not. Using their onboard weather radar or guidance from air traffic controllers, pilots will always navigate around thunderstorms — or simply turn around.
Hurricanes, however, are not always as disruptive to flights as a thunderstorm can be. “As far as aviation goes, most tropical systems and hurricanes are, generally, not as tall as traditional thunderstorms,” said meteorologist and pilot James Aydelott. “The tallest convection in a tropical cyclone is usually clustered around the central core of rotation, whether that’s just a low pressure, or in a hurricane, an eye,” he explained. This enables airlines to file flight plans that actually operate over parts of a hurricane.
Lightning through the window of a Malaysia Airlines Airbus A330 over Kuala Lumpur in 2010. Photo by SAEED KHAN/AFP/Getty Images
For obvious reasons, no commercial aircraft is ever going to penetrate the eyewall of a hurricane. We leave that distinct honor to the brave men and women on board hurricane-hunter aircraft of the US Air Force and the National Oceanic and Atmospheric Administration. As you get further away from the eye of the hurricane, though, flight conditions become more and more manageable. Unlike with many thunderstorms, flights can safely navigate over the top of a hurricane or tropical storm with little impact.
“Each storm is different, but down low, near the eye, where the C-130 and P-3 ‘Hurricane Hunter’ flights fly, there is often turbulence,” said Aydelott. “High above, from all accounts I’ve seen, the ride is smooth. As far as flying goes, there should be no issues flying above a hurricane in an aircraft equipped to monitor radar echo tops.”
While Hurricane Florence was raging over the mid-Atlantic coast of the US, one particular flight caught the attention of aviation watchers. An Allegiant MD-80 operating between Bangor, Maine, and Orlando, Florida, took a shortcut over the top of the hurricane while all other flights went around the edges. This raised some eyebrows, but it was perfectly safe.
“Allegiant Airlines 2237 flew well above Hurricane Florence on Friday, September 14, and was not affected by the storm,” said Federal Aviation Administration spokesperson Paul Takemoto. “All air carrier flights file flight plans, and receive air traffic control service for the entire flight. Air traffic controllers direct flights around or above severe weather. They do not direct flights through severe storms.”
A screenshot from FlightAware of the Allegiant flight going over Hurricane Florence at 34,000 feet.
While flights above hurricanes can be perfectly safe, they do require a bit of extra planning and attention to detail. “If you needed a diversion for maintenance or medical, your options are a bit more limited, but from a cruise altitude, you have a lot of airports even further on the storm’s fringe to divert toward,” said Aydelott. While many flights will simply opt to travel around the storm, doing so is not actually required.
As weather predicting and sensing technology improves over time, and as pilots are able to receive more and more real-time weather data while in flight, navigating around and over storms can become more commonplace. For now, most flights will be routed around hurricanes while a few will opt to take a bit of a shortcut right over the top.
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|To: TimF who wrote (1458)||9/21/2018 5:53:10 AM|
|From: S. maltophilia|
|We flew through the edge (or so we were told) of a typhoon over the western Pacific once. About half an hour of rather severe turbulence. I never knew a 747's wings were so flexible, flapping what seemed like at least a couple yards at the tips, and i spent a lot of time mentally reviewing everything I knew about metal fatigue.....|
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|To: S. maltophilia who wrote (1384)||9/21/2018 8:36:43 AM|
|American Airlines Adopts Stricter Requirements for Emotional Support Animals|
American Airlines will require all passengers traveling with emotional support animals and psychiatric service animals to provide documentation of proof of health or vaccinations a minimum of 48 hours in advance of the departure of a flight effective as of Sunday, July 1, 2018, according to this article which was released yesterday.
In developing the updated requirements, American Airlines consulted with its disability advisory board and disability advocacy groups and organizations — such as My Blind Spot, Incorporated — to ensure that the expanded policy accommodates guests with disabilities. This initiative is all while remaining in compliance with the Air Carrier Access Act. For new flight reservations which are booked on or after Sunday, July 1, 2018, passengers who travel with emotional support and psychiatric service animals must submit three completed documents via e-mail message or fax to American Airlines:
Mental Health Professional Form — Currently required, this is a letter issued by a mental health professional or medical doctor approving the use of an emotional support and psychiatric service animals.Animal Behavior Guidelines Form — A signed affidavit affirming the emotional support or psychiatric service animal is trained to behave in public and that the owner accepts all liability for any injuries or damage to property.Animal Sanitation Form — For flights greater than eight hours in duration, documentation is required stating that your animal will not need to relieve itself or can do so in a way that does not create a health or sanitation issue. A Trend in the Commercial Aviation Industry American Airlines follows the lead of Delta Air Lines — and then United Airlines and Alaska Airlines — in being prompted to to strengthen its policies pertaining to passengers who travel with emotional support animals.
Although most animals do not cause problems, the changes were derived by American Airlines to ensure a safe environment for all passengers and were developed based on a number of recent incidents over the most recent few years during which the inappropriate behavior of emotional support animals has impacted and even injured employees, other passengers and legitimate service animals, as caused by what is described as a steady increase in incidents from animals who have not been adequately trained to behave in a busy airport setting or aboard an airplane.
The changes do not apply to the policy of American Airlines pertaining to traditional service animals.
Owners and handlers are required to keep animals traveling with them under their control at all times; and all animals must behave well in a public setting.
Passengers with tickets purchased after Sunday, July 1, 2018 who do not submit the required documentation a minimum of 48 hours in advance will be offered to fly with their pet under existing policies for travel in the cabin or in the temperature-controlled cargo compartment. Existing fleet and breed restrictions — as well as health certificate requirements — will apply.
Animals Which are Not Permitted to Travel on American Airlines American Airlines does not accept the following exotic or unusual animals to be misidentified as emotional support animals or psychiatric service animals:
A Reminder of the Definitions of Service Dogs and Emotional Support Animals The official definition of a service animal — according to the Disability Rights Section of the Civil Rights Division of the Department of Justice of the United States pertaining to the Americans with Disabilities Act, or ADA — is as follows:
- Sugar gliders
- Non-household birds — farm poultry, waterfowl, game birds, and birds of prey
- Animals which are improperly cleaned and/or has an odor
- Animals with tusks, horns, or hooves — except miniature horses that are trained to behave appropriately
Service animals are defined as dogs that are individually trained to do work or perform tasks for people with disabilities. Examples of such work or tasks include guiding people who are blind, alerting people who are deaf, pulling a wheelchair, alerting and protecting a person who is having a seizure, reminding a person with mental illness to take prescribed medications, calming a person with Post Traumatic Stress Disorder (PTSD) during an anxiety attack, or performing other duties. Service animals are working animals, not pets. The work or task a dog has been trained to provide must be directly related to the person’s disability. Dogs whose sole function is to provide comfort or emotional support do not qualify as service animals under the ADA. Additionally, service animals must be harnessed, leashed, or tethered — unless these devices interfere with the intended work of the service animal or the disability of the individual prevents using these devices. In that case, the individual must maintain control of the animal through voice, signal, or other effective controls.
This definition does not affect or limit the broader definition of “assistance animal” under the Fair Housing Act or the broader definition of “service animal” under the Air Carrier Access Act.
Some State and local laws also define service animal more broadly than the ADA does. Information about such laws can be obtained from the State attorney general’s office.
An emotional support animal is a companion animal which provides therapeutic benefit to an individual designated with a disability — such as depression, bipolar disorder, panic attacks or anxiety as only a few of many examples. While only dogs — and, in a separate provision which need not be discussed here, miniature horses — can be officially designated as service animals, emotional support animals can also be cats and other animals as prescribed by a physician or other medical professional if the owner of the animal has a verifiable disability in accordance with federal law of the United States.
In order to prevent discrimination by commercial airlines — based both within and outside of the United States — against passengers on the basis of physical or mental disability, the Air Carrier Access Act was passed by the Congress of the United States in 1986; and here are where complaints may be registered against an airline via the official Internet web site of the Aviation Consumer Protection and Enforcement division of the Department of Transportation of the United States.
Employees of airlines are limited by law to the questions they are permitted to ask owners of animals brought aboard airplanes. Only two questions may be asked by employees of an airline — or of any other company, for that matter pertaining to service animals…
…and when the service an animal provides is not obvious, an employee of an airline or other company cannot do the following actions without violating federal law:
- Is the dog a service animal required because of a disability?
- What work or task has the dog been trained to perform?
Official Policies of Airlines in the United States A commercial airline is permitted to require a passenger traveling with an emotional support animal provide written documentation that the animal is an emotional support animal — unlike for a service animal. A fee does not apply to service animals of passengers with disabilities — not even on airlines such as Spirit Airlines and Allegiant Air, which are known for their proliferation of ancillary fees.
- Ask about the nature of the disability of the person
- Require medical documentation
- Require a special identification card or training documentation for the dog; or
- Ask that the dog demonstrate its ability to perform the work or task
Here is a list of airlines with links to their official policies pertaining to animals:
Inside Take What American Airlines, Alaska Airlines, United Airlines and Delta Air Lines are implementing can be considered a step in the right direction; but although the new requirements may mitigate the number of passengers who attempt to cheat the system — which is not fair to passengers who have legitimate service dogs or emotional support animals — the effort will not be enough to eliminate them, as those passengers who are determined to fraudulently pass their pets as legitimate service dogs or emotional support animals will continue to do so to save money.
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|From: TimF||2/20/2019 8:31:52 AM|
| A Commercial Flight Hit an Absurdly Fast 801 MPH While Flying Over the United States|
A Virgin Atlantic flight making the grueling journey from Los Angeles to London yesterday hit a ground speed of at least 801 mph, thanks to a streak of fast-moving air in the jet stream over Pennsylvania. You’re probably wondering how, as breaking the sound barrier over land is illegal, but despite surpassing the speed required to break the sound barrier, there was no sonic boom.
And no, the Virgin Atlantic flight wasn’t in some super-special mystery jet that you haven’t heard of. And no, they’re not bringing the Concorde back. Here’s what happened.
The 801 mph ground speed of the Boeing 787-9 was reported on the flight tracker system Flight Aware, and was tweeted out by meteorology teacher Stu Ostro:
The typical cruising speed for a plane of this size is only around 560 mph, which is a long way off of the speed of sound’s 767 mph (although the speed of sound does vary based on altitude, air temperature, pressure, and on and on, and that 767 mph figure is based on a reading at sea level under standard conditions).And that’s exactly why there was no sonic boom for this 801 mph flight. I’ll let the Washington Post explain:
With a speed max currently over central Pennsylvania, airplanes flying through the jet will either be sped up or slowed down big time, depending on their direction of travel. It’s like the moving walkway at the airport. You have your own forward speed, but if you continue this velocity in an environment that is itself moving, it can propel you at an impressive rate.So the plane, in this case, was essentially carried along at those speeds by the air around it, so that while it’s ground speed was faster than the speed of sound, its air speed was not. Otherwise the stress of flying near or over the speed of sound would add significant strain on the body of the plane and its control surfaces, and potentially spell disaster. If a plane isn’t meant to go faster than the speed of sound, then it really, really shouldn’t.
Commercial aircraft ordinarily can’t break the sound barrier, because they’re not designed to handle the sudden increase in drag and other aerodynamic effects associated with those speeds. Despite a ground speed that high, the plane didn’t come close to reaching that threshold because it was embedded in the swiftly moving air.?
Despite not being in the jet stream over the northeast very long, the plane managed to arrive 48 minutes early in London, and most flights headed east over this area of North America are expected to have shorter flight times in the coming days. Of course, any flight going the other direction will either have to fight the wind or go around, so they’re expected to have longer flight times.
The jet streams winds are typically faster-moving in the winter, the Post reports, because of the maximized temperature differences between the northern and southern parts of North America...
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|To: cruisingtime who wrote (1453)||9/20/2019 4:13:42 AM|
Since it sounds like you are renting your own boat you have a ton of options. It really depends on what you are looking for. The places you mentioned are all great. (I haven't been to Makarska but have heard good things). But they are all pretty popular. There are a lot of islands where you can get off the beaten track if that is how you want to travel. Split is a must in my opinion. It is one of my favorite places in Croatia.
If you are wanting a sailing tour there are a few companies I know. Busabout does a sailing Croatia tour. But it is geared more towards backpackers. There are also a lot of tour agents where you can find a tour to meet your needs.
This is a great post for reading about the best islands in Croatia that might give you some more insight.
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