washingtonian From , joined Dec 1969, posts, RR: Posted (3 years 1 week 5 days 23 hours ago) and read 4334 times:
I watched the NOVA special last night. I have some random questions:
One of the theories they suggested is that the A-330s weather radar picked up the first small storm, but that this small storm blocked the airplane's radar from seeing the much larger storm behind it. I guess my question is what is the normal procedure for when an airplane encounters a thunderstorm over the ocean. If they are supposed to fly a certain path and only are in HF radio contact once an hour or so, how do they know they are not flying into more dangerous territory or another airplane's path? Is the standard procedure to try to raise ATC on HF to report their new path?
Also, it appears from all of those images that the particular storm was spread over dozens of miles. So is there really any way for an airplane to go around a storm like this?
Last question: What about the 10 or so other airliners that were flying across the Atlantic that night? Did they all fly around the storm, or what?
UTAH744 From United States of America, joined Jul 2009, 176 posts, RR: 0 Reply 1, posted (3 years 1 week 5 days 22 hours ago) and read 4182 times:
I did a quick google search to find a reference for you and the first one I came up was from India which is fine as all countries adheare to world-wide procedures. In general if you need to deviate from your assigned track and are unable to contact ATC as pilot in command you can deviate further than 10NM from tract by climbing or descending 500' and announcing on either 121.5 or 123.45 your position and your intentions. The link below tells the correct procedures, just scroll down to 11.6.8.
washingtonian From , joined Dec 1969, posts, RR: Reply 2, posted (3 years 1 week 4 days 18 hours ago) and read 3533 times:
Quoting UTAH744 (Reply 1): I did a quick google search to find a reference for you and the first one I came up was from India which is fine as all countries adheare to world-wide procedures. In general if you need to deviate from your assigned track and are unable to contact ATC as pilot in command you can deviate further than 10NM from tract by climbing or descending 500' and announcing on either 121.5 or 123.45 your position and your intentions. The link below tells the correct procedures, just scroll down to 11.6.8.
Interesting...I assume other aircraft did this that night?
PPVRA From Brazil, joined Nov 2004, 8767 posts, RR: 42 Reply 4, posted (3 years 1 week 4 days 17 hours ago) and read 3382 times:
IIRC the program did say that for that effect to happen, you need to approach the small storm from an angle that would block the bigger storm behind it. If the other aircraft weren't at just the right angle they may have seen the storm and then gone around it.
"If goods do not cross borders, soldiers will" - Frederic Bastiat
DogBreath From United Kingdom, joined Mar 2008, 251 posts, RR: 0 Reply 5, posted (3 years 1 week 2 days 8 hours ago) and read 2806 times:
The airlines I've flown for have always made very good use of satellite imagery and at the flight planning stage you are made aware of the potential weather issues on your planned track. Especially when flying across the ICTZ, you know that there will be CB's and thunderstorms to contend with. I have no idea how AF conduct their flight briefings and what resources they use to assess weather, but in my experience you are always prepared. Of course weather is an ever constantly changing phenomenon and can improve or deteriorate very quickly. You need to have your wits about you and be prepared to deviate. The most I've had to deviate was approx 95nm off track and once had to make a 180 degree turn to find another route through the weather as the radar wasn't able to penetrate the first CB and show further lines of CB's behind the first. I'm no stunt pilot and would never intentionally fly through a CB or TS. And until the CVR/FDR are recovered from the AF flight there will be no absolute 'conclusive' proof that these AF pilots did the same.
You mention in your question about how do you change path if only in contact on HF every hour. You are always in contact with ATC, even on HF. Of course nowadays most airlines have ACARS. If you need to deviate for weather then it's quite simple to get on the radio and get a deviation clearance. If using ACARS it's even easier by sending an ACARS message.