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During preflight this morning I came across an interesting NOTAM:

SGH 11/011 SGH AIRSPACE HIBAL SGH202011 E BND REACHING FL600
WEF 0911141600-0911141800

So what does HIBAL stand for ?

HIBAL is the Notam contraction for high altitude balloon. Most likely, a National Weather Service balloon with radiosonde.   A radiosonde is a small device that is suspended about 80 feet below a 6 foot hydrogen or helium balloon.  The radiosonde consists of sensors and a small radio transmitter.  The sensors are able to read temperature, pressure and relative humidity.  The on board transmitter sends this data back to sensitive ground based equipment for recording.  By recording the GPS coordinates (if equipped) and the direction of the data using radio directional finding antennas, it is also possible to record wind speed and direction.

To learn more about Radiosondes and their uses, NOAA National Weather Service has put together this radiosonde fact sheet.

Back to the NOTAM:

SGH 11/011 SGH AIRSPACE HIBAL SGH202011 E BND REACHING FL600
WEF 0911141600-0911141800

This NOTAM says that between 1600 Zulu and 1800 Zulu on the 14th of November, a high altitude balloon (HIBAL) is being released on the SGH VOR radial 202 at 11 DME (202011).  The balloon is expected to go east bound and reach 60,000 feet (FL600).

Fly Safe.

Christian writes with a simple enough question we have all wondered at some point in our training:

Hello. I’m a student pilot. Could you do me favor please? Tell me the KBXK ASOS or AWOS and how to get it? Thanks in advance.

Hi Christian.  Thanks for your question.  Here are three quick ways to find the type of weather station for any given airport:

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This is one of those questions that everyone has asked at one point or another. Whether you are a pilot or a passenger, we all have wondered what would happen if the airplane that I’m flying would suddenly be hit by lightning?

In private pilot ground school we learned that friction causes drag.  What we may not have been told is that this same friction also creates static electricity.  As an airplane flies through the air it continuously creates a static charge, especially on the aircraft control surfaces.  This situation is only made worse when flying through any kind of precipitation or even worse, volcanic ash.   Static wicks which are attached to the trailing edges of control surfaces are designed to help dissipate this charge to the surrounding air.  Static wicks protect not only our flight instruments and radios but also the flight surfaces themselves.  Without the static wicks attached, the static charge on the surface would try to “jump” the unconductive control hinges to the rest of the aircraft.  This “jump” or arc could cause permanent damage to the surface itself if the static charge had the opportunity to build sufficiently.  To further protect against this damaging “jump”, manufacturers also attach conductive bonding strips to keep the static build-up to a minimum.

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Have you ever wanted a quick and easy way to get text weather (METARs, TAFs and NOTAMs) for a selected airport from one website?

This can be handy if you are wanting to check weather at an airport before a training flight or perhaps a flight just around the traffic pattern.   Maybe you don’t need a full weather briefing, to file a flight plan, or even weather graphics; all you need is some basic text weather.  Well I finally found a quick and easy way to get METARs, TAFs and NOTAMs for multiple airports using a single webpage AND it works on a mobile phone as well.  Are you ready? The URL is:

http://www.fltplan.com/Cell.htm

Although it is designed to be used primarily to get aviation weather from a mobile phone, I like using this URL from my regular computer and browser.  It just provides for me a good way to check the weather at single or even multiple airports without the fuss of having to sign in.   This in  no way replaces my official and required weather briefing, but if you just need an update on that briefing, I think that fltplan.com/cell offers a neat solution.  No clicking, no selecting radio boxes, just type the airport indentifiers and you’re done!

Again:

http://www.fltplan.com/cell.htm

If you are looking for a good comprehensive flight planning and aviation weather package for the Apple iPhone, I strongly recommend you take a look at the products offered by ForeFlight.

Take a look at this METAR:

KSGH 021156Z AUTO 28006KT 7SM UP CLR M03/M06 A3004 RMK AO2 FZRANO 50006 60000 T10271061 10000 21027 UPB26 P0000 SLP181

Any idea what the contraction “UP” stands for?  That is “unknown precipitation”.  You’ll see another mention of unknown precipitation near the end of the report, “UPB26″  That means that the unkown precipitation began at 26 past the hour and in the case of the METAR quoted above, that would be 1126Z.

Something else about this METAR report which is unique: FZRANO.  This stands for Freezing Rain (FZRA) information is not available.  Most likely this is due to an issue with the observation station (although I’m surprised there isn’t a “$” at the end of the report. That symbol <$> would indicate maintenance is needed on the observation station).

Ok, just a couple of quick things I wanted to show you from my weather report this morning…back to my preflight!

Fly Safe!

Funny story for you with humor that only a pilot may understand. I was checking the ASOS at my home airport on the way in tonight and I heard something interesting on the radio:

Automated weather, time 2156 zulu, winds 290 at 9, visibility 10, sky clear, light rain, temperature 22, dewpoint 16, altimeter 30.22

Sky Clear and Rain? I’m confused. I’m not sure where the rain came from? I sure didn’t see any. Now here is the really funny coincidence, as I was listening to the radio on the way home, Creedence Clearwater Revival came on singing, “Have you ever seen the rain?” Now if you aren’t familiar with the lyrics, let me quote the chorus for you:

I want to know, have you ever seen the rain?
I want to know, have you ever seen the rain?
Comin down on a sunny day?

No, CCR, I haven’t seen the rain come down on a sunny day, but it sure wasn’t for the lack of trying.

Now, to turn this into an educational experience, I’m going to add a quick lesson. How do you seriously know when an ASOS might be reporting inaccurate or corrupted data? You can look for a “$” sign at the end of the METAR report. Here’s an example:

260256Z AUTO 19007KT 8SM FEW080 22/19 A3002 RMK AO2 56010 T02220194 LTG DSNT NW-NE SLP158 $

You know from the $ sign at the end of the report that maintenance is needed on the weather station system making this report. That is the station’s way of saying, “I’m in need of some attention.” You don’t know what is broke but you know that something may be inaccurate. I would recommend trying to find another surface observation in the area and compare it to the other to make sure they are reporting somewhat similar weather.

Fly Safe.

I was looking at some crazy midwest weather today at the Aviation Weather Center and noticed an interesting note in the “Top News”. Apparently, on November 5, 2008 the Terminal Aerodrome Forecast (TAF) will change from a 24 hour forecast period to new format to support a 30 hour TAF.

A quick background information about what a TAF is. A TAF stands for Terminal Aerodrome Forecast. It is a standard weather product that pilots use to look at forecasted weather over the next 24 hours. It will tell pilots what the prevailing weather will be in terms that are important for pilots such as wind, cloud ceiling and visibility. Pilots use this weather product to make determination about what kind of instrument approach they will use at an airport and if they have to file an alternate airport if they can’t make it into their primary airport.

I did a little more research on this new TAF rule and found that this is being done because of some of the factors affecting long haul carriers. Imagine if you an airline pilot and you are trying to plan a 14-18 hour flight. If you have a 24 hour TAF that was issued 4 hours ago, you wouldn’t know the weather at the time you are proposed to land! That’s no good. So now we have 30 hour TAFs to help those long haul guys out.

The FAA took a look and determined that only 32 of the biggest airports in the country will need a 30 hour TAF but to keep all TAFs the same they have determined that all TAFs (even the 24 hour ones) will be in this new format.

I looked at a sample of this new TAF format. It seems the big difference is the addition of the date to the time group. Here is a sample 24 hour TAF in the new format:

KABC 131128Z 1312/1412 14005KT P6SM OVC040
TEMPO 1312/1316 OVC025
FM131600 13015G23KT P6SM OVC015
FM132100 13015G22KT P6SM OVC008
TEMPO 1321/1401 1SM -SN
FM140100 09015KT 3SM BR OVC006
TEMPO 1401/1405 2SM -SN BLSN
FM140500 01015KT 5SM BR OVC006=

As you can tell there is a little extra clutter in there that extra clutter is the date! If you can figure out the first line, the rest of it is easy.

KABC 131128Z 1312/1412 14005KT P6SM OVC040

This forecast which was prepared on the 13th of the month at 11:28 Zulu is is valid from the 13th at 12:00 Zulu to the 14th at 12:00 Zulu. Let’s look at a sample forecast period:

TEMPO 1321/1401 1SM -SN

This forecast line says that temporarily (less than 2 hours) between the 13th at 21:00 Zulu and the 14th at 01:00 Zulu the weather will be 1 statue mile with light snow. See, no problem! Just teach yourself to think of the first 2 digits as dates and all will be well!

If you would like to learn some more about this new forecast the FAA has provided some websites for you to visit. Only one problem. The urls they provided are all in upper case and they only work in lower case! So I converted them all to lower case for you to use without a problem.

A listing of all the affected TAFS:

http://www.weather.gov/os/aviation/pdfs/30_hr_taf_tables.pdf

A FAA explanation of the 30 hour TAF and TAF testbed:

http://www.weather.gov/os/aviation/taf_testbed.shtml

National Guidelines regarding the TAF will be included in an appendix as part of a future update of NWS instruction regarding TAFS:

http://www.nws.noaa.gov/directives/sym/pd01008013curr.pdf

And finally, if you are a forecaster and want to know how to edit the new TAF format (there is a nice graphic there for users as well)

http://aviationweather.gov/notice/taf30.php

Fly Safe (even if you are flying for 18+ hours)

As reported in this month’s Flying Magazine, the National Weather Association (NWA) is offering a free online weather theory course.   It is designed to help general aviation pilots understand how weather theory affects flying.
When you go to their website (see links below) you will find they currently offer two “modules”  An introduction module and an aircraft performance module.  To begin you download each module to your computer.  You are actually downloading a zip file which contains an executable file that will launch a  Macromedia Shockwave presentation.  Each download is roughly 22 megabytes.  The introduction module goes over:

• Moisture
• Vertical Motion
• Stability

The aircraft performance module goes over…well, how weather affect aircraft performance.

I found both tutorials and courses to be extremely informative and highly educational.   The aircraft performance is very through and goes through many different aircraft performance scenarios and how weather would affect that situation.    I also learned from their website that they are planning on releasing two more courses Aviation Weather Forecasts and Application of Weather Theory.  I look forward to both additional courses.

My only complaints about this course would be that it is advertised as online and really you download the course which makes a “offline” course and also the menu and navigation were a little bit clumsy.  Once you start a section, you can’t stop it.   I actually had to use CTL-ALT-DEL and the task manager to end it when I had to stop it mid course.

You can check it out and review it for yourself at http://www.nwas.org/committees/aviation/WeatherTheory/

Enjoy.  I look forward to hearing your comments about the course.