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CB / TS - during approch and landing

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CB / TS - during approch and landing

Old 25th Jul 2012, 09:16
  #41 (permalink)  
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big operator in middle east

min 3nm horisontal seperation below 1000 agl

anybody have anything ?
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Old 25th Jul 2012, 09:38
  #42 (permalink)  
 
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What a bunch of idiots those pilots.
They are visually going into a thunderstorm,tower advising them of low vis and ts overhead of airport,lightning in sight,and yet they press on with no escape route.
At one a point when the rain starts increasing and possibly turbulence,one pilot starts to giggle,a proof of unconscience and or plain stupidity.
It is as bad as those muppets from aeroflot taking off with snow on wings..

PENKO,

If you enter rain and your wx radar picture is all red, then reduce the gain to see the shape and position of the TS /cbs.

Last edited by de facto; 25th Jul 2012 at 10:07.
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Old 25th Jul 2012, 19:31
  #43 (permalink)  
 
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This will put hairs on your chest.

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Last edited by LYKA; 26th Jul 2012 at 09:25.
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Old 1st Aug 2012, 12:22
  #44 (permalink)  
 
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Hey fellow aviators
I'd like to get your opinion about the use of the airborne weather radar.Two days ago i was flying(737NG) at FL350 on the 40NM scale with the Tilt on Auto it was indicating -2 and the whole picture was just weather Red,yellow and some green and it was in such a way that we couldn't even differentiate the ground returns from weather,knowing that the weather in that part of the world(africa) doesn't cover the entire route the only options were to divert much longer or return back,my skipper then set the radar on Manual ant selected a Tilt on 0 then +1 and we had minimal returns and we carried on the flight as planned and there was no weather as opposed to what the Auto tilt was showing.My question is setting the Tilt on 0 when at cruising level the optimum way to asses weather?Any comment is appreciated.Thanks
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Old 1st Aug 2012, 19:16
  #45 (permalink)  
 
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Setting the tilt at 0 or +1 at higher cruise altitudes for short distance evaluations is asking for trouble. Think about the composition of a TS at normal jet cruise altitudes (hint: radar reflectivity doesn't show frozen moisture well) and you could be "grossly" user-estimating the strength of the cell...if its painting at all. What you had in the first instance (auto-tilt setting) sounds about right.

Last edited by LYKA; 1st Aug 2012 at 19:21.
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Old 2nd Aug 2012, 05:58
  #46 (permalink)  
 
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You sound very correct Lyka,well so far we passed through with no bumps and whatsoever but i'll be srutinizing more the radar concept.The Autotilt was showing us we couldn't pass through at all according to the display
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Old 2nd Aug 2012, 11:10
  #47 (permalink)  
 
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Always tried to stay 10nm from a CB especially on the downwind side because of hail falling out of the overhang....
It's a gamble... once diverted 300nm off track before we realised we were avoiding ground returns.
Think the boys on the 1-11 were the bravest as they flew the Berlin corridor - no deviations allowed especially after the Russkies shot up Air France.
Wx radar is only a guide as have flown through cells which didn't paint but were extremely active.....and vicky versa
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Old 4th Aug 2012, 17:53
  #48 (permalink)  
 
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-2 degree 80 and 40 mile range.

I have developed a method of working the radar that requires constant changes in range and angle. There is no one set angle or distance. With a -2 degree, and a 40 mile range any return that continues inside the 30 of less range needs to be considered. working with the angle, never really staying at one angle with valid threats around, one can get a rough idea of what is ground return and what isn't. Much can be added with vision during the flashes of light and short term memory situational mental mapping. And a regular change of angle to -1 and the 80 or 160 mile range will prevent proceeding into a dead end valley of storms.

And I also change the settings from auto to min and max to get a well rounded summary of returns when in the battle.

And as an aside, I have noticed quite a difference in the various radar returns on different aircraft, even those supposedly with the same radar. Some appear to over read when in auto.

And another thing I have done...when new to an area...even when cavok, I turn the radar on and learn what the local terrain looks like on the radar screen for future reference.

There have been times over the gulf of Mexico on flights between puerto rico and costa rica, when there were virtual walls of storms through which we had to thread needles with the radar on the closest range possible, with an occasional scan out further to make a longer range plan. Just last month we had a similar night over Austria in which the controller had everyone separated via flight levels and he told us to manuever as required and only call when clear to return to flight plan path...the frequency was jammed with heading changes.

The two videos...I would not have made that approach and landing unless I had already used up all my fuel and had no other options. The other video, I would have given a bit more clearance from that big red storm off to the right. He shaves the edge of it...I couldn't see the wind direction...but it did appear a bit closer than I would have liked.

And remember, who is really in charge in the heat of the battle. I have made some very large deviations, even recently, when the entire coast of Spain and France were lined with immense build ups. Of course I do put direct to my destination runway and try to make a compromise in the total distance traveled and the required deviation. Whilst avoiding, I update the fmc route to check destination fuel, even using airports on the map that match my chosen deviation and joining those to whatever flight plan remains. No apologies, but when I am in charge of the airplane and storms are about and the battle is on, I "tell" ATC what heading I will fly...unless of course the cells are well spaced and I will tell them I can go left or right so many degrees and give them the option.

Last edited by stator vane; 4th Aug 2012 at 18:03.
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Old 4th Aug 2012, 18:25
  #49 (permalink)  
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Our Company SOPs...remain 3NM clear of any CB on final approach.

Have graded avoid distances at medium and high levels (20NMs from a return at 30,000' plus). This is talking about DOWNWIND distances though. A TS notionally moves in the direction of the 10,000' wind and upwind clearance (from a turb and hail clearance point of view) is much less.

As someone said as you get closer you will see more red (the gains are artificially increased from NASA et als datum gains). Long story related to product liability claims and does not indicate a rapid increase in activity in the last minute.
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Old 6th Aug 2012, 19:19
  #50 (permalink)  
 
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@stator vane,i totally agree with you when you said the radar gives you an overestimated picture from the normal,in this case when you're in a situation where you can't differentiate from ground returns to weather is using the tilt in manual the best option?I'm asking because i've tried it the other day as i took the radar to manual i tilted it slightly up -1 and some of the returns disapeared we passed through with no shakes.
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Old 10th Aug 2012, 10:21
  #51 (permalink)  
 
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Work that angle!

Like our life depended upon it.

And apologies for my earlier post with a few mistakes...firstly, the original post is titled approach and landing...I covered the entire flight regime! Ha! And the ranges were mis-typed...on the 80 mile range, with a -2 degree, if a return passes inside of approximately 50 miles, I consider it a threat to be avoided. With a sighting on a regular interval out to 160 with a -1 degree. And when in battle, I vary the gain from auto to full to min with varying angles to get the best picture I can, whilst keeping a good look outside for those helpful flashes and momentary visuals which are godsends! Especially at night.

As for determining the ground return, studying the returns at various angles will give you the best solution, keeping in mind the surrounding terrain you are in...hopefully you will have some idea...ground return should be rather uniform at the same range...if there is a lone round-ish or scalloped return all by itself, it is either a mountain or a build up...both to be avoided.

It is definitely a continual learning process! Again, I suggest using the radar when it is cavok to get familiar with your base's ground returns at various angles and approaches.
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Old 1st Sep 2012, 12:38
  #52 (permalink)  
 
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ASSUMING THE RADAR {OPERATOR} WORKS?

1. How many of us perform a "confidence check" on the radar before we launch into known CB activity areas?

2. How many companies SOPs call for such a check?

3. The radar "test" facility does NOT necessarily prove it will transmit and therefore receive a useful return.

4. IMHO weather radar management and use is one of the worst taught skills in the industry, assuming the company has ANY disseminated info.

5. Most of the skills are picked up second hand from whichever Grumpy Old F**t is in the left seat who may have "his own way" of operating this valuable kit.

6. We will continue to see microburst/TS accidents and hail damaged aircraft lucky to land until the issue is addressed by those who decide the priority of TRAINING.

7. As long as there are crews who believe that switching the radar on in some aircraft "wears it out", when flying the NG for example {!} then that demonstrates the abysmal lack of knowledge on the subject.

8. A bright cavok day when there is low workload and time to develop one's skills is the occasion to learn more about the kit, it's limitations and it's benefits, maybe better use of one's paid time than reading the paper and preferable to trying desperately to learn when the screen is turning all four colours and the turbulence and precipitation are the first perceived alerts?!

9. Next time boredom approaches halfway through the flight, play with the kit using ground returns and get familiar with the controls. The relatively new "auto" tilt setting I believe will instill a false sense of security and lead some into trouble.

10. There are still capts around who believe the tilt setting is zero with the aircrafts pitch axis and not the real horizon-as long as these myths persist then we're in a state of ignorance and potential misinterpretation.

P S Anyone who believes it scares birds away, ask why the feathered fraternity were happy to frisk around in front of military PAR assemblies and still go on to breed happily, despite the much higher power and radhaz energy emitted by these installations?
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Old 1st Sep 2012, 12:40
  #53 (permalink)  
 
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ENTERED IN ERROR!

Brain fade- entered in error whilst trying to edit.
Grey matter fried by too much use of Wx radar.........................

Last edited by BARKINGMAD; 1st Sep 2012 at 12:44. Reason: Double entry accidental.
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Old 1st Sep 2012, 19:11
  #54 (permalink)  
 
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As long as there are crews who believe that switching the radar on in some aircraft "wears it out", when flying the NG for example {!} then that demonstrates the abysmal lack of knowledge on the subject
How about in climb and descent?

8. A bright cavok day when there is low workload and time to develop one's skills is the occasion to learn more about the kit, it's limitations and it's benefits, maybe better use of one's paid time than reading the paper and preferable to trying desperately to learn when the screen is turning all four colours and the turbulence and precipitation are the first perceived alerts?!
Agree.

Last edited by de facto; 1st Sep 2012 at 19:12.
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