B777 Collins Wx Radar On/off Switch?

[CaptWilliam 0]

I have been going over the B777 flight crew training manual, but I can't find how you active and de-activate the Wx radar beam.

Is this automatic, like is this connected to the squad switches?

 

Having the radar beam on at the gate is not a good idea.

 

 

Willem

[Gokau 4]

I believe the WXR button on the EFIS control panel is the weather radars on and off switch.

[scandinavian13 5,192]

I believe the WXR button on the EFIS control panel is the weather radars on and off switch.

 

This is correct.

[CaptWilliam 0]

Thanks,

just found this at pprune.org forum to back this up:

 

quote
There is a separate control panel but on/off function is through the EFIS control panel.

endquote

 

Strange that I cant find this in Boeing documentation, LOL.

 

Willem

[scandinavian13 5,192]

 

 

Strange that I cant find this in Boeing documentation, LOL.

 

I think it might be because there are different radar options, and they weren't sure how the individual manufacturer would implement it.

[AlanB77L 0]

There's a little mention in FCOM Vol. 2 page 10.10.41. I'd copy and paste if I could, but the reference will have to do  ^_^

[Don t moderate me this way 882]

P. 675 ...

[CaptWilliam 0]

Thanks Guys,

I found it now; I was expecting this under the Wx radar documentation.

 

Willem

Just to show that the Wx radar is not a light tpoic, I want to share this::

From a survey held under RW Captains ,average age 52 with 12K+ hours:

 

• 62 percent of the pilots surveyed answered correctly that a straight radar beam is not aligned with an aircraft’s current flight level (because of Earth curvature)

• 15 percent mistakenly thought that antenna down-tilt was required to offset a nose-up pitch angle. (That is offset by antenna stabilization.)

• 63 percent did not appreciate the need for weather-radar antennas to be set to compensate for earth curvature, which blocks weather targets beyond, say, 150 nm ahead for nominal cruise altitudes. “Curvature [effects] become noticeable at ranges above 40 nm, and if ignored can lead to weather-image interpretation errors,” said Khatwa.

• 55 percent of pilots did not realize that a weather target falling inside the radar beam will not necessarily be shown in its true color on the display. “The color selected for display is a direct function of the power returned to the receiver. Where the beam is partially filled, the total power returned may not represent the calibrated value associated with the target cell,” he said.

• Five in every eight pilots incorrectly thought green (short-range) radar targets shown near to cruise levels above FL310 need not be avoided. “Typically, at these altitudes, targets are less reflective. At high altitudes, there is a possibility of unstable air and hail above the storm cell. It is therefore not advisable to penetrate the less-reflective part of the storm top,” Khatwa explained.

• 73 percent of flight crew understood that antenna tilt angle does not need to match a climb (or descent) angle to detect weather on their flight path. “The antenna should be pointed at the base of convective weather during climb. Generally, the lower 18,000 feet is the most reflective part of the storm.” Radar can be used to analyze weather characteristics (such as vertical extent of cells) and to avoid strong convective activity. “Returns along the flight-path angle may not provide full indication of storm intensity and turbulence levels [to be encountered within the cell].”

• Almost 90 percent of pilots did not know the range at which their current weather radar was no longer calibrated and did not show returns at their true levels. Radar beams broaden with distance, so a smaller proportion is filled with moisture. “At shorter ranges, returned power is more representative of the target cell, and it is more likely to be displayed at its true calibrated value. Typically, returns are calibrated within a range of 60 to 80 nm.”

[scandinavian13 5,192]

 

 

From a survey held under RW Captains ,average age 52 with 12K+ hours:

 

...and this is why I always tell people "just because they fly the thing doesn't make them experts!"  I'm not saying "don't believe a thing a pilot says," but take information from anyone with a grain of salt.

 

I always love the "well I asked [such and such pilot] the same question and he said you're wrong!!!"  All the while, I'm quoting directly from the regs...  :rolleyes:

 

 

 

• 15 percent mistakenly thought that antenna down-tilt was required to offset a nose-up pitch angle. (That is offset by antenna stabilization.)

 

That one got me, too, honestly.

[CaptWilliam 0]

Today I found out that the auto button is actually pretty cool.

I was climbing out on a departure with a 5 degrees ANU attitude, The FPV showed 3 degrees.

And the radar beam info on the ND showed -2. i.e. it is scanning along the proper flight path, how cool is that?

 

Willem

[Michael Moe 494]

i just had to because its so great :

 

Kyle said:

.and this is why I always tell people "just because they fly the thing doesn't make them experts!"  I'm not saying "don't believe a thing a pilot says," but take information from anyone with a grain of salt.

 

Me:

So great because it tells the story between the ideer (the king right ? (the Aviator)  and the man.

 

Thanks

 

Michael  

[maf 10]

Thanks Guys,

I found it now; I was expecting this under the Wx radar documentation.

 

Willem

Just to show that the Wx radar is not a light tpoic, I want to share this::

From a survey held under RW Captains ,average age 52 with 12K+ hours:

 

• 62 percent of........................

 

As a current ATPL-student (europe that is), that stuff was fantastic! Ive now learned more about WX-radars than my atpl textbook has been able to do in 2 pages!

 

Where did you get this survey?

 

Thanks for sharing!

[CaptWilliam 0]

pprune.org is your friend

 

http://www.pprune.org/archive/index.php/t-376731.html

 

You might like this too as you are an aspiring RW pilot:

 

The beamwidth of the 737 weather radar is 3.5 degrees.

To calculate the height of the cloud tops above your altitude use the following formula:

 

Cloud tops above a/c (ft) = range (nm) x (tilt - 1.5 deg) x 100

 

eg Wx at range 40nm stops painting at +2deg tilt. The tops would be 40 x 0.5 x 100 = 2000ft above your level.

 

 

Willem

[maf 10]

pprune.org is your friend

 

http://www.pprune.org/archive/index.php/t-376731.html

 

You might like this too as you are an aspiring RW pilot:

 

The beamwidth of the 737 weather radar is 3.5 degrees.

To calculate the height of the cloud tops above your altitude use the following formula:

 

Cloud tops above a/c (ft) = range (nm) x (tilt - 1.5 deg) x 100

 

eg Wx at range 40nm stops painting at +2deg tilt. The tops would be 40 x 0.5 x 100 = 2000ft above your level.

 

 

Willem

 

 Fantastic! Thank you so much for this!