Aviation Weather Services

Hi Readers: Aviation Weather Services promolgated by the FAA, the NWS, and NASA are best described by and necessarily involve the actual flight, local or x-c, VFR and IFR flight plans; beginning with flight planning, and leading to en route flight, and terminating with descent and approach to land. In addition, the Weather Services provide an assist to the Controllers in preparing for the duties in which they are charged. Even local flights must be considered in terms of current weather - often pilots on local flights are caught in a sudden change of weather from VFR to IFR, as many of the aircraft accidents reveal.
Weather is a 24-hour phenomenom, in constant change of its elements and phases. In 20 minutes a cloud ceiling may ascend or descend 2,000 feet, precipitation can change from rain to ice, and visibilities can become obscured or obliterated.
Since most weather services are tied to a specific phase of flight, let's plan a VFR x-c flight. Without getting into the details, we would either file a flightplan with AFSS/FSS by telephone using TIBS (Telephone Information Briefing Service), a recording of the destination current weather, or talking with a weather specialist concerning the destination current and forecasted weather (1-800-WxBrief- toll free). This is a Preflight Briefing to help the pilot determine a "go" or "no go" decision. Or, if you are computer-oriented, you may file a flight plan with DUATS(Direct User Access Terminal System) - toll free, and get alpha-numeric preflight weather data and file a domestic VFR or IFR flight plan.
We might use, in conjunction with our flight plan or separately, METAR (Aviation routine weather report) or an FA(an area forecast), if advantageous.
After takeoff, we are considered in an en route phase of flight and can utilize several services to our advantage.
Lest we forget, we can still communicate with AFSS/FSS on a common frquency of 122.2 or a discrete frequency for an individual station to file, activate, close, or change a flight plan; request an IFR clearance, contact ATCT/ARTCC for control; file position reports, pass PIREPS (Pilot weather reports); request status of Special Use Airspace; and request assistance in an inflight emergency.
Normally, we might use EFAS (En Route Flight Advisory Service) for nonroutine weather needs in flight or TWEB ( Transcribed Weather Broadcasts) for the routine weather needs in flight. Inflight advisories include SIGMET (Significant Meteorological Information), Convective SIGMETs, AIRMETs (Airmen Meteorological Information), FAs (Area Forecasts) , Winds Aloft Forecasts (176 locations in 48 States), and PIREPs (Reports by pilots of weather conditions in flight).
Descending from en route flight to approach and landing at our destination we might use any number of weather advisories, primarily that concerning the weather at the destination airport or terminal such as FA, LLWAS (Low level wind shear alert system), PIREPs, TAF(Terminal Area Forecast), and WW (Severe Weather Watch). And, of course, our continued communications, depending on VFR or IFR, with ARTCC, TRACON ( Terminal Radar Approach Control), ATCT, and following with GT (Ground Control) to the very end of our flight.
ATCT and TRACON both use air/ground communications, visual signals, and other devices to provide ATC services to aircraft operating in the vicinity of an airport. ATC services authorizes aircraft to land or takeoff at the airport controlled by the tower or to transit the Class D airspace area regardless of flight plan or weather conditions. A tower may also provide approach control services.
To put the aviation weather services in perspective, the pilot must deal with ARTCC, ATCT, and TRACON (as spelled out in AC 00-45F) with respect to their flight plan to effect location and positive control of the aircraft. TRACONs manage the airspace 10 to 400 miles outside of selected airports and below 13,000 feet. They also coordinate spacing as aircraft approach and depart airports. Terminal Controllers are knowlegeable of current weather conditions and are prepared to advise pilots of hazardous weather conditions within a 150 nm sector or area. Tower operators are certified to act as official weather observers.
The December 2007 aircraft Accident Accounting is in process.
Thanks for listening. R.S.

PIREPS

Hello Readers: Before we get to PIREPS, have you thought about your weight lately? Do you know what your Body Mass Index is? BMI will give you a good indication of where you stand on weight. This through the courtesy of Karen Miller-Kovach, RD, Chief Scientific Officer of Weight Watchers In'l, the formula: Divide your weight, multiplied by 703, by your height in inches squared. You should comeout somewhere between 20 and 30. 20 to 30 - optimal, 25 to 30 - overweight, and 30+ - Obese.
Now the PIREPS - What are they? Get out your Acronym reader.
Pilot reports are inflight, usually en route, weather reports to help other inflight pilots know what is up ahead of them. You can check PIREPS either prior to your takeoff or en route. Or if need be, you can contact the pilot directly to ask his assesment of the weather. Normally you would contact your FSS (Flight Service Station) and get EFAS (En route Flight Advisory Service).
EFAS (Flight Watch) is a service specifically designed to provide, upon pilot request, timely weather information pertinent to type of flight, intended route of flight, and altitude. This service is within the FSS system, and is listed in any Airport/Facility Directory.
FAA, through the air traffic facilities, is required to solicit PIREPS when the following conditions exist - reported or forecast:
1. Ceilings at or below 5,000 ft.
2. Visibility at or below 5 miles - surface or aloft.
3. Thunderstorms and related phenomena.
4. Icing conditions of a light or greater degree.
5. Turbulence of a moderate degree or greater.
6. Wind shear, reported or forecast, and volcanic ash clouds.
Pilots are urged to cooperate and volunteer reports of cloud bases, tops and layers; flight visibility; precipitation; visibilitity restrictions such as haze, smoke, or dust; wind at altitude; and temperature aloft.
PIREPS should be given to EFAS, AFSS/FSS, ARTC (Air Route Traffic Control), and terminal ATC. The EFAS (Flight Watch) facilities, as mentioned, has the specific duty of collecting and exchanging PIREPS with en route aircraft. If pilot are not able to make PIREPS by radio, then the reports should be given to the local FSS upon landing.
Some of the uses of PIREPS areas follows:
ATCT (Tower) uses the reports to expedite the flow of air traffic locally.
AFSS/FSS uses the reports to brief other pilots inflight and en route.
ARTC uses the reports to expedite the flow of en route traffic.
NWS (National Weather Service) uses PIREPS to verify or amend conditions contained in Aviation Forecasts and Advisories, and pilot weather briefings.
There are numerous pages of information in the FARs regarding PIREPS, their importance, and specifically how to prepare and use them. Pilots should take the time to digest this information in the FARs, with the idea of participating in PIREPS. Thanks for listening. R.S.