Study the instrument rating by connecting rules rather than collecting them: one forecast window (ceiling at least 2,000 feet above airport elevation and visibility at least 3 statute miles across the ETA hour) drives both the alternate-filing exception and the alternate fuel exception, alternate selection uses separate thresholds that published procedure minima can override, and holding entries come from a 70/110/180-degree diagram read against your arrival heading.
Why the 2,000-Foot Ceiling Is Measured Above Airport Elevation, Not Above Approach Minima
Under 14 CFR 91.169(b), a Part 91 airplane may omit the alternate only when an applicable instrument approach serves the destination and forecasts show a ceiling at least 2,000 feet above airport elevation and visibility at least 3 statute miles from one hour before through one hour after ETA.
The thresholds are fixed numbers anchored to airport elevation. They are not computed by adding 2,000 feet to the approach's decision altitude or 3 miles to its published visibility. An ILS with a 200-foot DA and half-mile minimum neither raises nor lowers the filing window; a qualifying forecast at a sea-level airport qualifies by the same standard as one at a high-elevation field. Separating the filing exception from approach minima in your notes prevents the two rule families from bleeding together.
Worked scenario: the destination sits at 1,200 feet elevation with an ILS (DA 200 feet) and half-mile visibility; the forecast across the ETA window is 3,500-foot ceilings and 5 miles. The tempting mistake is computing '2,000 above DA' and concluding 3,500 fails. The better decision: compare 3,500 against elevation plus 2,000 (3,200) and 5 against 3, so the exception applies — no alternate is required and, by the matching fuel rule, no alternate fuel leg. Misreading this either wastes a perfectly good alternate or grounds a legal flight.
Fuel to Destination, Alternate, and 45 Minutes: Applying 91.167 Without Double-Counting
14 CFR 91.167 requires a Part 91 airplane in IFR conditions to carry fuel to the first airport of intended landing, then to the alternate airport if one is required, then for 45 minutes at normal cruising speed.
The 45-minute reserve rides on every IFR flight; what flexes is the middle term. When the 91.169(b) weather window is met at the destination, 91.167(b) removes the alternate fuel leg, because the two sections share the same exception conditions. Study them side by side so a forecast change flips both conclusions together: once the window fails, you both re-list an alternate and re-add its fuel. Keeping one annotated copy of the two rules on a single page makes that linkage visible every time you review.
Labeled study example: cruise burn 10 gallons per hour, destination 2.0 hours away, alternate 0.8 hours away. With the exception met, the rule's minimum is (2.0 + 0.75) × 10 = 27.5 gallons; without it, (2.0 + 0.8 + 0.75) × 10 = 35.5 gallons. Treat this as study arithmetic, not a dispatch release — real planning adds wind, taxi, and personal margins. The purpose of the exercise is to see which term appears and disappears as the weather window opens and closes.
Filing IFR to an Airport With No Published Approach: What the Rules Actually Permit
Nothing in 91.169 requires an approach at the destination. A 2015 FAA legal interpretation confirms you may file IFR to an approach-less airport when an alternate is listed, and 91.205(d)(2) separately requires navigation equipment suitable for the route flown.
The Chief Counsel's 2015 letter answers two related questions. First, filing to an airport without a Part 97 approach is allowed provided the plan includes an alternate — the exception in 91.169(b) is optional relief, not a precondition to filing. Second, equipment cannot be borrowed from the alternate: an alternate equipped with approaches the aircraft can fly does not satisfy 91.205(d)(2)'s requirement that the aircraft carry navigation equipment suitable for the route to the destination itself.
An alternate without its own published approach is also possible, but 91.169(c)(2) sets the bar: reports or forecasts must allow descent from the MEA, approach, and landing under basic VFR at your estimated time of arrival. When sketching practice flight plans, mark which candidate airports have approaches, because destination and alternate are evaluated under different paragraphs with different thresholds — one window governs whether you must list an alternate, and another governs whether a given airport is legal to list.
Choosing a Legal Alternate: When 600-2 and 800-2 Are Not the Answer
The familiar 600-2 (precision) and 800-2 (nonprecision) figures are defaults that apply only when the procedure publishes no alternate minima of its own; published minima replace the standard ones, and the check applies at your arrival time at the alternate.
Read the instrument approach procedure itself before defaulting to the generic numbers. 91.169(c) says the alternate must meet the minima specified in the procedure, or, if none are specified, the standard values. A procedure can publish higher or differently structured alternate minima, and an airport with no approach falls under the basic-VFR criteria instead. Building the habit of checking the procedure notes — rather than recalling the defaults first — is what makes this decision reliable under exam time pressure.
Worked scenario: your proposed alternate offers only an RNAV (GPS) approach whose notes publish alternate minima of 1,000-2. The forecast at your alternate ETA is an 1,100-foot ceiling and 3 miles. The tempting mistake is applying the generic 800-2 nonprecision default and filing it without a look. The better decision: the published 1,000-2 governs; 1,100 and 3 still clear it, so the alternate is legal — but a 950-foot forecast would not be. A nominally familiar alternate that fails its own minima is exactly the compounding error these flight-planning questions are built to reveal.
The table below gathers the airplane Part 91 thresholds from this article into one comparison you can rebuild from memory.
| Rule family | What it decides | Airplane threshold | Source |
|---|---|---|---|
| Omitting the alternate | Whether the destination needs an alternate listed | Part 97 approach at destination plus forecast ceiling at least 2,000 ft above airport elevation and visibility at least 3 SM, ETA minus 1 hour through ETA plus 1 hour | 14 CFR 91.169(b) |
| Alternate minima (approach published) | Whether a specific airport is legal to list | Minima published in the procedure, or defaults of 600-2 (precision) / 800-2 (nonprecision) at the alternate ETA | 14 CFR 91.169(c)(1) |
| Alternate minima (no approach) | Whether a non-approach airport is legal to list | Weather allowing descent from the MEA, approach, and landing under basic VFR | 14 CFR 91.169(c)(2) |
| Reserve fuel | How much fuel the IFR plan must carry | Destination, alternate leg when required, then 45 minutes at normal cruising speed | 14 CFR 91.167 |
Holding Entry From the 70/110/180 Picture, Not From Compass Mnemonics
Draw the pattern, mark the inbound course and the holding side, then divide the remaining space: a 110-degree parallel sector and a 70-degree teardrop sector, with a 180-degree direct sector, judged against your heading upon arrival.
Each sector maps to one procedure. Parallel entry: turn outbound on the non-holding side to parallel the inbound course, then turn in the direction of the pattern to rejoin inbound. Teardrop entry: fly outbound on a heading offset 30 degrees from the outbound reciprocal toward the holding side, then turn in the pattern direction to intercept the inbound course. Direct entry: proceed to the fix and turn to the outbound course. The sector widths — 110, 70, and 180 degrees — tell you which procedure your arrival heading calls for.
The confusion that produces wrong entries is between the inbound course, your heading, and the direction from which you approach the fix; these are easy to swap under pressure. Fix it by labeling a hand sketch every time: inbound course to the fix, the reciprocal flown outbound, the holding side determined by turn direction, and your heading at arrival drawn as an arrow. Compare your sketch against the AIM's holding diagram rather than testing memory phrases, so the geometry itself becomes the recall cue.
Worked Holding Scenario: Arriving Along the Inbound Course
Paper scenario: a standard right-turn hold with a 360-degree inbound course at a VOR, arriving at the fix on a heading of 360. This arrival follows the inbound course and lies in the direct-entry sector. The diagram therefore indicates a direct entry into the published pattern.
Draw the fix and the northbound inbound arrow first, then draw the aircraft approaching from the south on heading 360. Its heading matches the inbound course; the outbound reciprocal is 180. The tempting error is confusing the direction from which the aircraft comes (south) with its heading (north), which can invert the entry classification. The better paper-study decision is to compare the arrival arrow with the current AIM diagram and identify the direct-entry sector before describing the pattern. Keep this as a diagram exercise and confirm your interpretation with an instrument instructor or simulator session.
The FAA recommends its entry procedures because the holding protection areas were developed with those procedures in mind. Other entries can remain within protected airspace; do not treat every different entry as automatically illegal or as a traffic conflict. For paper practice, label the inbound course, outbound reciprocal, holding side and arrival heading, then compare your diagram with the AIM. A correct answer explains those labels and the selected sector rather than relying on a memorized compass shortcut.
A Self-Check Rubric and Six-Week Sequence for These Rule Families
Run a weekly cycle: draw three holds from invented fixes, compute one fuel plan, and classify one alternate, scoring each task against stated thresholds instead of a feeling of readiness.
Exercise: from an en route chart excerpt or your own sketches, create three holds with different inbound courses, turn directions, and arrival headings; write your predicted entry before checking the geometry. Expected observations: predictions slip near sector boundaries — an arrival heading only 20 to 30 degrees from the inbound reciprocal still falls in the direct sector, and a heading a few degrees past the 110-degree parallel edge flips to teardrop. Re-draw until your predictions match the sectors on three consecutive holds before moving on.
An adaptable sequence: weeks one and two, read 91.167 and 91.169 together and rebuild the comparison table from memory; weeks three and four, holding — daily sketch work plus the AIM's en route and holding section; week five, weather and approach procedures, practicing alternate selection from real procedure notes; week six, mixed problems combining all three under time. Scope your review against the current Instrument Rating – Airplane ACS on the FAA's Airman Certification Standards page; administrative details such as test scheduling live on FAA pages rather than here. You are ready to sit practice exams when every rubric line below scores consistently.
- Alternate exception: you can state the 2,000-feet-above-airport-elevation / 3-SM / ETA-plus-or-minus-one-hour window without ever adding approach minima into it.
- Alternate selection: you check the procedure's published alternate minima before reaching for the 600-2 or 800-2 defaults, and you know the no-approach basic-VFR fallback.
- Fuel planning: you identify which legs count in a given forecast, apply the 45-minute reserve, and recompute when the weather window opens or closes.
- Holding: you draw the 70/110/180 sectors to rough scale and correctly name the entry for five invented arrival headings, including reciprocal and boundary-adjacent cases.
- Integration milestone: given one forecast sheet, you can decide alternate requirement, alternate legality, and minimum fuel in a single pass with consistent conclusions across rules.
References and further reading
Use these references to explore the concepts and check the latest information from the relevant organizations.