Stepdowns on Instrument Approaches, What You Still Owe the Procedure When You Go Visual

Breaking out of the clouds during an instrument approach and acquiring the runway visually does not release a pilot from stepdown fix altitude requirements. Under 14 CFR Part 91, Section 175, the instrument approach procedure governs the operation until a formal transition to visual flight occurs - and stepdown fixes exist because of terrain, not weather. This distinction is one of the more consistently misunderstood points among instrument-rated pilots.

Why Stepdown Fixes Exist

Stepdown fixes appear on non-precision approaches because those procedures lack a continuous glidepath. Precision approaches provide an unbroken obstacle clearance envelope from the final approach fix to the runway. Non-precision approaches do not - they use a flat segment flown at the minimum descent altitude (MDA).

The terrain and obstacles along that flat segment don’t cooperate with a single uniform floor. Procedure designers identify what’s along the approach course, then publish a stepdown fix at the point where the aircraft has cleared whatever is in the way. Once past that fix, the next lower altitude provides clearance for the remainder of the segment.

A stepdown fix is not administrative overhead. It is the precise point where obstacle clearance math permits a lower altitude. Think of it as terrain telling the procedure where to put the floor.

What 14 CFR 91.175 Actually Permits

14 CFR Part 91, Section 175 governs operations below the MDA or decision altitude on an instrument approach. It permits descent below the MDA only when three conditions are simultaneously met:

• The aircraft is continuously in a position from which a normal rate of descent to the landing can be made
• Flight visibility is not less than the visibility prescribed in the instrument approach procedure
• The pilot has at least one specified visual reference in sight

Those visual references include the approach light system, the threshold, threshold markings, threshold lights, runway end identifier lights, the visual approach slope indicator, the touchdown zone or its markings or lights, and the runway or runway lights.

Meeting these three conditions authorizes descent below the MDA. It does not modify the altitude requirements at each stepdown fix before the MDA is reached.

Going Visual Does Not Terminate the Instrument Procedure

This is where the confusion concentrates. The authorization to descend below the MDA and the obligations created by stepdown fixes are two separate things.

The terrain a stepdown fix accounts for does not disappear when the clouds do. A tower, antenna, or ridge at 2,400 feet in the obstacle clearance area is still there regardless of visibility. Being visual gives pilots the ability to see and potentially avoid obstacles. It does not remove them.

Flying an instrument approach procedure means flying all of it - stepdowns included. Two things terminate the instrument procedure: canceling the IFR clearance, or accepting a visual approach clearance from ATC. Those are operationally distinct events. Until one of them occurs, the published altitudes at every stepdown fix remain binding.

Two Scenarios That Illustrate the Difference

Scenario one: VOR approach, stepdown fix two miles from the MAP, required altitude 2,400 feet, MDA 1,800 feet. Pilot breaks out at 2,800 feet with the runway in sight. No conflict. The aircraft is above the stepdown altitude, crosses the fix with margin, and continues normally.

Scenario two: Same approach. Pilot breaks out at 2,100 feet with the runway in sight and the required visual references. The stepdown fix is still ahead, requiring 2,400 feet. The aircraft is already 300 feet below the required altitude at that fix.

Visual conditions do not resolve this retroactively. Obstacle clearance along the published track was predicated on crossing that fix at or above 2,400 feet. The runway being visible does not change what exists between the aircraft and the threshold.

What a Visual Approach Clearance Actually Changes

Accepting a visual approach clearance from ATC is a genuine procedural transition. A visual approach is not an instrument approach procedure. The pilot assumes direct responsibility for terrain and obstacle clearance by seeing and avoiding rather than by following published minimums. Stepdowns from the underlying instrument approach no longer apply as a regulatory matter.

The responsibility that transfer creates is real. At an unfamiliar airport, accepting a visual approach without knowing the terrain environment means owning a problem the procedure would have solved. The FAA recommends - and many airline and corporate operations require - that crews reference the published approach plate even on visual approaches. Not because the stepdowns legally govern, but because the plate identifies the obstacles. It functions as a terrain map regardless of approach type.

A pilot cannot claim the protections of the instrument procedure while selectively bypassing the altitudes the procedure requires. The two are not separable.

RNAV Approaches and the Stepdown Question

On RNAV approaches with vertical guidance - LNAV/VNAV or LPV - the stepdown question is largely moot. A continuous glidepath handles obstacle clearance throughout the descent, and the vertical deviation indicator keeps the aircraft on it throughout.

On LNAV-only approaches and older RNAV approaches without vertical guidance, stepdown fixes function exactly as they do on conventional non-precision approaches. The same rules apply: cross them at or above the published altitude. Visual conditions do not change that obligation while the instrument procedure is active.

Circling Approaches

On a circling approach, once the aircraft breaks out above the circling MDA and begins maneuvering to a different runway, the stepdowns on the final approach course have typically already been passed. The operative floor becomes the circling MDA, and the aircraft must remain at or above it until established in a position to make a normal descent to the runway.

Circling minimums are higher than straight-in minimums because the procedure accounts for obstacles across the entire circling radius around the airport. Breaking out below the circling MDA removes procedural protection in an environment where the aircraft may be maneuvering close to terrain - and that is where circling approach accidents occur.

Why This Matters for Pilots

Instrument approach procedures are engineering products. Every altitude, fix, and minimum produced by the FAA’s instrument flight procedure office reflects an evaluation of terrain, obstacles, signal quality, and aircraft categories. Flying the procedure means operating inside a tested protection envelope.

Departing from the procedure - crossing a stepdown below the published altitude, drifting off centerline, cutting a fix - puts the aircraft outside that envelope. Visual conditions improve the odds of detecting a threat. They do not eliminate the threat or restore the clearance the procedure provides.

The procedural and the visual are two separate dimensions of the same flight. Neither replaces the other.

Key Takeaways

• Stepdown fixes encode obstacle clearance, not arbitrary restrictions. Each fix marks the point where procedure design says a lower altitude is safe.
• 14 CFR 91.175 authorizes descent below the MDA when visual references and visibility requirements are met. It does not override stepdown altitude requirements.
• Going visual does not end the instrument procedure. Only canceling the IFR clearance or accepting a visual approach clearance from ATC does.
• A visual approach clearance transfers obstacle clearance responsibility to the pilot. The approach plate remains a valuable terrain reference even then.
• LNAV-only RNAV approaches carry stepdown fixes with the same authority as conventional non-precision approaches - vertical guidance is what makes them moot, not GPS technology alone.