FAR Ninety-One Point One Hundred Three, the 'All Available Information' Standard Every Pilot in Command Is Held To, and the Preflight Briefing That Has to Be More Than a Weather Check

FAR 91.103 is one of the most powerful regulations in general aviation - and one of the most consistently underestimated. It sits near the top of Part 91, it applies to every pilot in command on every flight, and it sets the legal floor beneath everything else in your preflight.

What Does FAR 91.103 Actually Say?

The key sentence reads: “Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight.”

Four words carry the legal weight here. “Shall” - not “should,” not “is encouraged to.” In regulatory language, shall removes all discretion. And “all” - not weather information, not safety-related information, not relevant information. All available information concerning that flight.

The regulation then gets specific. For flights not in the vicinity of an airport, and for any flight under Instrument Flight Rules (IFR), the required items are: weather reports and forecasts, fuel requirements, alternatives if the planned flight cannot be completed, known Air Traffic Control (ATC) delays, airport information, runway lengths at airports of intended use, and takeoff and landing distance data.

What Does “All Available Information” Mean for Weather?

A quick check of the METAR (Aviation Routine Weather Report) at your departure airport is not “all available information.” The regulation requires understanding weather conditions along your entire route, at your destination, at your alternates, and - critically - at the times you will actually be at those locations.

A complete weather picture includes the area forecast, winds aloft forecast, any SIGMETs (Significant Meteorological Information) or AIRMETs (Airmen’s Meteorological Information) along the route, PIREPs (Pilot Reports) from aircraft that have recently flown that airspace, and current and forecast conditions at your destination and alternates.

Scrolling through a radar loop and deciding the green looks acceptable does not satisfy this regulation. An official briefing through 1-800-WX-BRIEF, a DUATS system, or a product like ForeFlight or Garmin Pilot connected to an official weather service puts you in the right direction - but only if you actually review what comes back.

Why Do NOTAMs and TFRs Matter for 91.103 Compliance?

NOTAMs (Notices to Air Missions) are required preflight information. If there is a NOTAM affecting your flight and you did not check it, you were not familiar with all available information. That is a regulatory violation regardless of outcome.

Temporary Flight Restrictions (TFRs) are issued by NOTAM. Flying through a TFR because you skipped the NOTAM check creates two stacked violations: the TFR violation itself and the failure to comply with 91.103. Pilots blunder into TFRs around major sporting events, dignitary movements, and wildfire operations with regularity - and in nearly every case, the information was available days in advance.

The FAA’s standard is not whether you made an effort. The standard is whether the information was available. If it was, you were required to know it.

Are Performance Calculations Legally Required?

Yes. Runway lengths and takeoff and landing distance data are explicitly listed in 91.103 - not as best practice, but as a legal requirement for cross-country flight.

Before flying to an unfamiliar airport, that means looking up the runway length, elevation, slope, and any departure path obstacles. Then opening your Pilot’s Operating Handbook (POH) and computing actual takeoff and landing distances for that day’s actual conditions: your pressure altitude, temperature, and aircraft weight at the time of landing - not standard sea-level numbers.

Consider a flight to a mountain airport with a 3,500-foot runway. A Cessna 172 may land well under 1,000 feet under sea-level standard conditions, which seems to leave enormous margin. But at 5,800 feet elevation on a hot July afternoon with full fuel and two passengers, the actual landing distance at that pressure altitude and temperature is substantially longer. The runway may still be adequate - or it may not. That answer has to come from the charts, not from a mental estimate on short final.

The calculation might prompt you to leave fuel behind, depart earlier before density altitude peaks, or choose a different airport entirely. These are decisions that can only be made before you commit.

What Are the Fuel Requirement Details?

Being familiar with fuel requirements means knowing three things: how much fuel is needed to reach your destination, how much reserve you are legally required to carry under FAR 91.151, and how much fuel is actually on board when you depart.

The minimums under 91.151 are:

• VFR day: 30 minutes of reserve at cruise speed
• VFR night: 45 minutes
• IFR: 45 minutes at the destination airport, plus enough fuel to reach an alternate if one is required

These are legal minimums, not targets. 91.103 requires familiarity with your fuel requirements - your specific airplane, your actual fuel burn at cruising altitude, your distance, your wind correction, and your actual fuel on board versus what you actually need.

Does the Alternate Requirement Apply to VFR Pilots?

It does. The regulation does not limit the alternates requirement to IFR operations. It applies to every pilot in command. If you are flying VFR and your destination airport deteriorates below VFR minimums before you arrive, do you have a plan? Do you know the weather at airports within your remaining fuel range?

If the answer is no, you were not familiar with all available information about your alternatives. This is a section of the preflight that VFR pilots routinely skip - and the regulation does not give them an exemption for it.

How Does 91.103 Show Up on a Practical Exam?

The examiner will ask you to walk through your cross-country planning. The standard they are measuring against is this regulation. Can you show weather information obtained from an authorized source? Can you walk through your fuel calculations? Can you show performance computations for your departure and destination airports? Do you have an alternate plan?

The Airman Certification Standards (ACS) for the private pilot certificate require you to demonstrate the ability to obtain performance data and compute distances for a cross-country flight. 91.103 requires that you actually do it before every flight you take as pilot in command. These are the same thing: the ACS tells you what the examiner will ask, and the FAR tells you what you are legally obligated to do for the rest of your flying career.

How Do I Use 91.103 as a Preflight Checklist?

Run down the listed items like a checklist before every cross-country:

• Weather reports and forecasts - full route, destination, alternates, at the times you will be there
• Fuel requirements - computed for your actual airplane, not the ballpark
• Alternates identified, weather obtained - VFR pilots included
• Known ATC delays - checked
• Airport information at destination - reviewed
• Runway lengths at destination - confirmed
• Takeoff and landing distances computed for actual conditions - done

If you can say “check” to every item with actual documentation, you have satisfied the regulation - not just checked a box.

This standard applies to every flight, not just cross-countries. For a local pattern session on a clear summer afternoon, “all available information” may genuinely take five minutes to review. The regulation does not require an hour of briefing for a short hop. It requires that you become familiar with whatever information is actually available and relevant.

But the habit has to be in place. The day you skip the brief on the “easy” flight is the day there is a TFR over the stadium ten miles downwind. “I didn’t think I needed to check” is not a defense when the NOTAM was published three days earlier.

Key Takeaways

• FAR 91.103 uses the word “shall” - preflight action is a mandatory legal obligation, not a suggestion, for every pilot in command on every flight.
• “All available information” includes weather along the full route, NOTAMs, TFRs, fuel calculations, runway data, performance computations, and alternates.
• Runway lengths and takeoff/landing distance calculations are explicitly listed in the regulation - opening the POH performance charts before a cross-country is not optional extra credit.
• Flying into a TFR after skipping the NOTAM check creates two stacked violations: the TFR penetration and a 91.103 failure.
• The ACS practical exam standard and the 91.103 legal standard are the same thing - demonstrating preflight planning to an examiner reflects what you are required to do for every flight you ever make.