radar tilt use
radar tilt use
Joined: Oct 2005
Posts: 3,218
Likes: 2
From: USA
Dave Gwinn is still very active in teaching and explaining radar. You might try his site...davegwinn.com. His basic course is available for a very reasonable price, comes with a booklet and CD, I think.
You could also try: Radar Tilt Management
If you really want to dive into the theory, the Archie Trammell course is still available out there. Buy lots of red bull in advance, though, because it's not physically possible to stay awake during the entire presentation without it. It's also pricey, so if you can find someone who's got it, so much the better.
You could also try: Radar Tilt Management
If you really want to dive into the theory, the Archie Trammell course is still available out there. Buy lots of red bull in advance, though, because it's not physically possible to stay awake during the entire presentation without it. It's also pricey, so if you can find someone who's got it, so much the better.
Joined: Aug 1998
Aviation Qualifications: ATPL
Posts: 6,623
Likes: 847
From: Ex-pat Aussie in the UK
Joined: Nov 2004
Posts: 1,324
Likes: 156
From: Here, there, and everywhere
www.
pirep.
org/forum/viewtopic.php?t=7286&sid=e02268cbb6d9bb861151299e6298444b
In conducting a survey about the RDR-4000 weather radar, Honeywell safety specialist Dr. Ratan Khatwa asked more than 50 ATP-rated pilots about their experience with weather radar. The average age of the respondents was 52 years; the average flight time was 12,500 hours. The answers these experienced pilots provided were illuminating.
• 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.”
Registered User **
Joined: Mar 2009
Posts: 480
Likes: 0
From: USA
Fe Hoppy
And don't fly into the red stuff! Avoide the yellow if at at all possible.
Flew with a captain (sorry for getting off subject) that was in rush to get to the hotel and justified flying the normal approach into EBRU through the red on the reasoning of his understanding that turbulance is less dramatic in the region. Half way through we experienced a hell of a static discharge, hope he thought it was fun.
Not very bumpy but it sure was a blast!!!
Flew with a captain (sorry for getting off subject) that was in rush to get to the hotel and justified flying the normal approach into EBRU through the red on the reasoning of his understanding that turbulance is less dramatic in the region. Half way through we experienced a hell of a static discharge, hope he thought it was fun.
Not very bumpy but it sure was a blast!!!
Joined: Mar 2001
Posts: 4,563
Likes: 35
From: I wouldn't know.
In our cpl training aircraft 10 years back we had a nice weather radar unit that had features i haven't seen in our shiny brand-new fail operational vertical situational display equipped 737. That old unit of course had vertical profile of the weather in front as well as target alerting of heavy weather beyond the current range selection. And all that in a small piston twin, a Seneca.
I've seen Honeywell now offers a successor to that unit for airliner operation that does volumetric scanning and uses an EGPWS database to suppress ground clutter, however i haven't seen that in operation and would be very interested if any airline at all uses that kit (RDR-4000).
I've seen Honeywell now offers a successor to that unit for airliner operation that does volumetric scanning and uses an EGPWS database to suppress ground clutter, however i haven't seen that in operation and would be very interested if any airline at all uses that kit (RDR-4000).
Joined: Feb 2006
Aviation Qualifications: ATPL
Posts: 490
Likes: 15
From: USA
Capt Gwinn's passing
Dave Gwinn is still very active in teaching and explaining radar. You might try his site...davegwinn.com. His basic course is available for a very reasonable price, comes with a booklet and CD, I think.
Sadly, Captain Gwinn is no longer with us.
Obituary
Guest
Posts: n/a
Greetings.
The first most important fact to know is that WX radar echoes on WATER IN LIQUID FORM, so wet snow, wet hail, rain, and most important WET WINDSHEAR, this is due to the fact that water molecule will align themselves when excited by microwave.
So where is the water in liquid form in a cloud? below ISO 0 deg, therefore the tilt has to be less than 0, you can use 1 in 60 rule, i.e., 1deg at 60 nm is 1 NM (6070 feet) so how many feet below your CRZ FL is the ISO 0?
baring in mind that WX range is 80 NM and Turbulence is 40 NM range.
The first most important fact to know is that WX radar echoes on WATER IN LIQUID FORM, so wet snow, wet hail, rain, and most important WET WINDSHEAR, this is due to the fact that water molecule will align themselves when excited by microwave.
So where is the water in liquid form in a cloud? below ISO 0 deg, therefore the tilt has to be less than 0, you can use 1 in 60 rule, i.e., 1deg at 60 nm is 1 NM (6070 feet) so how many feet below your CRZ FL is the ISO 0?
baring in mind that WX range is 80 NM and Turbulence is 40 NM range.
