KRYY Cobb County — Instrument Checkride Guide

What kind of airport is KRYY and what is its IFR environment?

Cobb County International Airport-McCollum Field (KRYY) sits at 1,040 ft MSL in Marietta, Georgia, approximately 21 nm northwest of Atlanta Hartsfield-Jackson (KATL). The airport has a single runway (09/27) measuring 6,295 ft × 100 ft with full ILS/DME equipment on the runway 27 end. McCollum Tower operates 0700–2300 local on 125.9 MHz; outside those hours, the airport is uncontrolled (CTAF 125.9 MHz).

Atlanta Approach Control handles all IFR traffic into and out of KRYY on 121.0 MHz. Because KRYY lies beneath several shelves of Atlanta Class B airspace, most IFR departures and some arrivals require Atlanta Approach coordination. Under 14 CFR 91.131, a specific ATC clearance is required before entering Class B airspace. On a filed IFR flight plan, that clearance is typically built into the departure clearance — but pilots must understand which airspace they are entering and at what altitude. ATIS broadcasts continuously on 128.125 MHz.

What instrument approaches are published at KRYY?

KRYY has 4 published instrument approach procedures, sourced from AirNav and verified against current SkyVector chart listings.

The ILS or LOC RWY 27 is the primary instrument approach. It provides precision guidance and the lowest published minimums to runway 27. Both RNAV (GPS) procedures may publish LPV lines of minima — always verify current minimums on official FAA charts before flight, as LPV availability depends on WAAS signal quality and GPS NOTAM status. The VOR/DME RWY 09 is the most basic procedure and requires functioning DME or a DME substitute.

What is the runway configuration at KRYY?

KRYY has a single runway, 09/27, measuring 6,295 ft × 100 ft with an asphalt surface. At 1,040 ft MSL elevation, density altitude calculations become relevant during summer operations. The 6,295-foot runway length is adequate for most GA aircraft operating IFR, but pilots should note that it is shorter than many nearby commercial-service airports used in checkride scenarios.

Tower notations include blasting operations within 2,000 ft of runway 27 on weekday mornings — check NOTAMs before flight. Landing fees apply to transient aircraft over 6,000 lbs and all transient operations between 2100–0600 local.

What weather should instrument pilots expect at KRYY?

KRYY's location at 1,040 ft MSL in the North Georgia foothills creates weather patterns distinct from Atlanta's urban core. Radiation fog is a recurring hazard from late summer through early spring: overnight cooling in the river valleys west and south of Marietta can produce dense fog that reduces visibility to near zero, sometimes while Atlanta Hartsfield (at only 1,026 ft MSL) remains marginal VFR. Pilots should check terminal aerodrome forecasts from the National Weather Service Peachtree City (FFC) office and obtain PIREPs from Atlanta Approach before departing into a foggy morning.

Summer convective activity develops rapidly along the North Georgia foothills from late afternoon into evening. Pop-up thunderstorms build over terrain to the north and northeast before tracking south toward the metro area. Cell movement can be fast — a cell that looks 30 nm away at departure can intercept your route within 20 minutes. Satellite imagery and NEXRAD interpretation, both evaluable ACS skills, become practical necessities at KRYY during June through September.

Winter weather in the Atlanta metro area is infrequent but operationally significant. Freezing rain events, locally called "ice storms," occur several times per decade and can coat runways and taxiways with ice within minutes of precipitation onset. KRYY has deicing facilities but they may have limited capacity during major events.

What should you expect on an instrument checkride at KRYY?

An instrument checkride departing KRYY requires careful situational awareness of the Atlanta Class B airspace structure from the first radio call. Most IFR departures climb through a Class B shelf — the DPE will note whether you understand where the shelf begins, what clearance authorizes you to enter it, and whether you comply with any altitude restrictions in the departure clearance. Confusing a Class C (Dobbins ARB is nearby) with a Class B shelf is a common knowledge-test error; knowing the specific altitudes and distances of the Atlanta Bravo floor near Marietta is a testable element of ACS Area I.

On the approach side, the ILS RWY 27 is the DPE's most likely primary approach. KRYY's single-runway configuration means the DPE cannot use runway selection as a variable — the approach direction is fixed by wind. In the event of a missed approach, expect Atlanta Approach to immediately issue vectors back into the Class B environment; pilots should be prepared to comply without hesitation.

The foothills terrain scenario in the airport-triads describes KRYY as a departure for a route to Athens-Ben Epps (KAHN). That routing crosses Georgia's Piedmont plateau and includes non-precision approaches at the destination — an ideal DPE setup to evaluate MDA versus DA concepts, step-down fixes, and circling approach minimums. Under 14 CFR 91.175(c), the visual references required before descending below MDA differ from those required before descending below DA, and the DPE may probe that distinction verbally before or during the approach.

The tower's 0700–2300 operating schedule also creates a planning element: a checkride scheduled near those boundaries tests whether the applicant understands how to obtain an IFR clearance when the tower is closed — either by telephone to Atlanta TRACON or via pre-filed clearance void time procedures.

Practice Questions

1. You are departing KRYY on an IFR clearance to KAHN. Atlanta Approach assigns an initial altitude of 3,000 ft MSL. You know a Class B shelf exists at 3,500 ft in the Atlanta metro area. How do you determine whether your assigned altitude is inside or outside Class B, and what regulation governs Class B entry?

2. You are flying the ILS RWY 27 at KRYY. At 800 ft AGL, you have the approach lights in sight but not the runway. Under 14 CFR 91.175(c), may you continue descending below DA? What visual references are required?

3. You arrive at KRYY at 2245 local and discover the tower is closed. Describe how you obtain an IFR clearance and what void time procedures entail under the AIM.

4. ATC assigns you the RNAV (GPS) RWY 09 with LPV guidance available. How does flying an LPV approach differ procedurally from flying the ILS RWY 27? What is the primary difference in how you identify the final approach fix?

5. During your post-landing debrief, the DPE asks why you briefed VOR/DME RWY 09 as a backup approach rather than RNAV (GPS) RWY 09. Explain the operational factors that might make a VOR/DME procedure preferable to a GPS-based approach.

Frequently Asked Questions

Q: What instrument approaches are published at KRYY?

KRYY publishes an ILS or LOC RWY 27, RNAV (GPS) RWY 09, RNAV (GPS) RWY 27, and a VOR/DME RWY 09. The ILS or LOC to runway 27 is the only precision approach. All procedures are sourced from AirNav and SkyVector current chart listings.

Q: Is KRYY inside Atlanta Class B airspace?

KRYY sits about 21 nm northwest of Atlanta Hartsfield-Jackson and lies beneath several shelves of Atlanta Class B airspace. Operations into and out of KRYY frequently require coordination with Atlanta Approach (121.0 MHz). Under 14 CFR 91.131, an ATC clearance is required before entering Class B.

Q: What is the tower operating schedule at KRYY?

McCollum Tower operates 0700–2300 local. Outside those hours, the airport is uncontrolled and pilots use CTAF 125.9 MHz. When the tower is closed, clearance delivery and ground services are also unavailable — IFR clearances must be obtained by phone or via DUATS.

Q: What runway is used for ILS approaches at KRYY?

Runway 27 is the only runway with a published ILS or LOC approach at KRYY. The 6,295-foot runway has full ILS/DME equipment. Runway 09 has RNAV (GPS) and VOR/DME approaches but no ILS.

Q: What are the communication frequencies at KRYY?

ATIS broadcasts on 128.125 MHz. McCollum Tower operates on 125.9 MHz (0700–2300). Atlanta Approach/Departure is 121.0 MHz. Ground control is 119.0 MHz. Clearance delivery shares 119.0/121.0 MHz when the tower is open.

Q: What weather hazards affect KRYY?

KRYY sits in the North Georgia foothills at 1,040 ft MSL. Radiation fog forms overnight in valley areas and can produce IFR conditions at the airport while Atlanta stays VFR. Summer afternoon convective activity is common, and winter ice storms occasionally affect the Atlanta metro area.

Sources

• AirNav — KRYY Airport Information
• SkyVector — KRYY Instrument Approach Procedures
• 14 CFR 91.131 — Operations in Class B Airspace (Cornell LII)
• 14 CFR 91.175 — Takeoff and Landing Under IFR (Cornell LII)
• FAA Instrument Flying Handbook FAA-H-8083-15B
• NWS Peachtree City (FFC) — Terminal Forecasts

This article was researched from FAA primary sources (ACS, FAR/AIM, Advisory Circulars, Instrument Flying Handbook), approach procedure data from AirNav and SkyVector, and citing current 14 CFR Part 91 — drafted by MockDPE Editorial Team. Last updated: May 2026. If you spot an inaccuracy, email corrections@mockdpe.org.