It may come as a shock to Plane & Pilot’s younger readers to learn that “in-cockpit weather” has actually been available for a very long time.
However, it wasn’t displayed on fancy flat screens. It was broadcast aurally from ground sources. Requiring only a pair of headphones and perhaps a sharp pencil with which to copy it, one listened and learned.
It probably wasn’t long after people started carrying radios around in aircraft that someone on the ground reported the weather to a curious pilot. And then aviators started asking if the station operator could read them the weather reports from places up ahead, so they could plan accordingly. That sure beat pounding blindly through a snowstorm in a U.S. Mail biplane and going down to take a look firsthand.
Following World War II, a network of VOR (VHF Omnidirectional Range) radio stations were installed across the U.S., establishing Victor airways and, with them, Interstate Airway Communication Stations (INSACS) manned by Civil Aeronautics Authority (CAA) personnel. These lonely outposts reported weather observations hourly via teletype, later becoming known as Flight Service Stations (FSS).
Each state might have had a dozen or more FSS facilities, usually colocated with a VOR station, over which they could communicate with aircraft. My 10-year-old Cessna 140 trainer’s four-channel transmitter had a “rock,” or crystal, tuned for 122.1 megacycles, the common FSS listening channel. A reply would come over the VOR’s frequency. This system still exists today at some VOR locations.
The VOR frequency was idle most of the time, so in the 1950s and ’60s the now-FAA weather briefers at the stations were put to work reading the list of current reports from their area’s teletype circuit, performed live by displacing the VOR’s Morse code identifier, precisely at 15 and 45 minutes past the hour. Thus, we pilots could tune into these scheduled broadcasts and get an update without having to call in for a customized report.
In-cockpit weather was now a regular thing.
The format was, in order, local station weather and NOTAMs, hourly weather for surrounding locations, a local forecast if available, winds aloft when available, and NOTAMs for nearby airports. The 15-after broadcast featured reports from terminals up to 400 miles away, while the 45-after report was a shorter-range scan of airports within 150 miles.
The only limitation to such scheduled reports was the VHF frequency’s line-of-sight shortcoming. Airplanes flying low to stay under the weather couldn’t receive them more than 25 miles or so from the VOR station. By the mid-’60s the outlying INSAC/FSS stations were being abandoned, their function consolidated into remote Flight Service Stations at only the larger cities, leaving fewer inputs available for scheduled weather reports. The live twice-hourly VOR broadcasts were first reduced to one, at 15 minutes after the hour, and then abandoned entirely.
What replaced them by the early 1970s was TWEB (Transcribed Weather Broadcast) service, a continuous recorded scan of area weather prepared on the hour, when the fresh reports came out. In addition to some VORs, the low-frequency beacon transmitters associated with NDB or ILS approaches would be used for the TWEB, since those were capable of being received at ground level at considerable distance from the station.
Back then, my day would start with turning on a low-frequency receiver in my bedroom and picking up the scan of current weather, forecasts, and NOTAMs. Low-frequency readability suffered during thunderstorm weather, however. If we had an ADF (Automatic Direction Finder) receiver on board, a common installation in the ’70s, we still had in-cockpit weather from the TWEB.
At about the same time, ATIS (Automatic Terminal Information Service) became available, a short-range recorded broadcast of routine information needed by aircraft arriving and departing tower-controlled airports, including weather. The recording was made fresh every hour by a live tower observer, or often if the weather was changeable, password-coded for confirmation of receipt.
Today, at some locations, artificial intelligence voices may bring you computer-generated ATIS info. TWEB broadcasts were eventually phased out, since there was no way to confirm how many people actually listened to them, and with improved radios pilots could pick up ATIS broadcasts at greater distances, even if they had no intention of landing at the megaplex airport.
By the turn of the 21st century, just about every little county airport was equipped with an AWOS weather station, now termed ASOS (Automated Surface Observing System) that reported the constantly-changing weather conditions. This gave pilots more sources of in-cockpit weather, available for the tuning, although it was limited by the low output of the ASOS transmitter. To check landing weather at long distances, it was still necessary to contact an FSS or friendly air traffic controller.
Which brings us to the present state of in-cockpit weather.
We now enjoy uplinked weather information available anywhere via SiriusXM Weather (developed in the early 2000s) or ADS-B In services (dating from the mid-2010s). Our flat-screen instrument panels or electronic flight bag tablets can instantly show us what’s being reported hundreds of miles away, or we can view radar pictures of precipitation that was recently present.
What I would have given for such capability when flying charter or cargo in the early years of my career.
