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Tail record, Bombardier Challenger 600 (Challenger 604), United States register

N604KJ: how this Bombardier Challenger 600 is flown

A Challenger 600 on long legs: fewer landings for its hours than three quarters of its type.

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Figures are for the twelve months to 31 Jul 2026; named aircraft are shown a week behind. Grades compare its record since 1 Jan 2025 with every tracked Challenger 600.

01

How N604KJ compares.

27 tracked flights in the twelve months to 31 Jul 2026.

Tracked flights

27

in the twelve months, about 2 a month

Days flown a month

2.3

in the months it flew

Estimated hours

≈53

in the twelve months, from time in the air

02

Month by month.

Its busiest month was June 2026, with 6 flights.

Tracked flights

Its busiest month was June 2026, with 6 flights. It did not fly in November 2025. The record has 17 tracking gaps, so about one flight in 2 may be missing and every count is a minimum.

Source: The Aircraft Ledger, flight data for N604KJ, the twelve months to 31 Jul 2026. Flight counts only: airports and exact dates are left out of this page.

03

The free chapter.

Each measure against all 763 tracked Challenger 600s. Every dot is one aircraft; the gold one is N604KJ.

Chapter 1

Fatigue

Gentler than its type

How short were its legs?

Utilization isn’t graded for N604KJ: too few of its flights were tracked to count its use fairly, in the full report too. So its free chapter here is Fatigue, which doesn’t depend on catching every flight.

More hours for each landing, so fewer pressurization cycles for its time in the air.

  • Hours per landingLead measure. 86th percentile

    2.4 : 1middle Challenger 600 1.8 : 1

  • Short hops53rd percentile

    35%middle Challenger 600 34%

  • Leg length65th percentile

    586 nmmiddle Challenger 600 494 nm

How its legs split

Share of N604KJ’s legs by length, nm, in the twelve months

Harsher means harder on the aircraft than three quarters of Challenger 600s; typical is the middle half. Percentiles compare this aircraft with every tracked Challenger 600, over its record since 1 Jan 2025.

04

What only the report shows.

The fleet is shown, and whether N604KJ sits inside its middle half. Its grades and values are in the full report.

Chapter 2

Corrosion

Salt air, middle Challenger 600: 2%

Also graded: damp air, freeze–thaw, near the coast and moisture in the air.

Not graded: not enough data.

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Chapter 3

Engines and brakes

Short runways, middle Challenger 600: 27%

Also graded: hot, high takeoffs; density altitude; dust and dry climate.

N604KJ sits outside the middle half, on one side or the other. Its grade and exact place are in the full report.

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Chapter 4

Utilization

Flights a month, middle Challenger 600: 6.1

Also graded: days flown a month and estimated hours a year.

Not graded: too few of its flights were tracked.

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05

The full report on N604KJ.

All four chapters, every flight since January 2025 leg by leg, and the one thing to ask the seller.

TailCheck report

N604KJ, Bombardier Challenger 600

$395one aircraft

  • All four chapters, graded
  • The one thing to ask, with records to request
  • Every flight since January 2025, leg by leg
  • Its weekly and seasonal rhythm
  • PDF, CSV and a share link; open for three months, kept up to date
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06

Questions about N604KJ.

Cite this data

The Aircraft Ledger. “N604KJ: how this Bombardier Challenger 600 is flown.” Data through 31 Jul 2026. theaircraftledger.com/aircraft/n604kj

How many hours does N604KJ fly a year?

About 53 estimated hours in the 12 months to 31 Jul 2026, across 27 tracked flights. Hours are estimated from time in the air, so the logbook has the exact figure.

How often is N604KJ flown?

N604KJ made 27 tracked flights in the 12 months to 31 Jul 2026, about 2 a month, and flew on about 2 days in each month it flew.

Does N604KJ fly internationally?

8 of its 27 tracked flights in the 12 months to 31 Jul 2026, 36%, crossed a border.

When did N604KJ last fly?

It was last tracked in July 2026. We publish an aircraft’s flights seven days after they happen, and show them by month only.

Why don’t you show which airports N604KJ uses?

We leave out airports, bases and exact dates on purpose. We show how an aircraft has been used, not where it goes.

What’s in the full TailCheck report for N604KJ?

All four graded chapters (Fatigue, Corrosion, Engines and brakes, and Utilization), each against the tracked Challenger 600s, plus the operational summary and operating rhythm, as a PDF, CSV and share link. It costs $395, or $995 a month for unlimited reports and Spotlight.

Fleet statisticsWhat’s normal for a Bombardier Challenger 600Buyer’s guideWhat to check before buying a used Challenger 600SpotlightCompare N604KJ with other Challenger 600s

Method: flight data, every count a minimum. Estimated hours from time in the air. About our data

Owners and operators can ask us not to publish an aircraft. Data policy and opt-out

Not a substitute for a pre-purchase inspection or records review. TailCheck shows how an aircraft has been used, not its condition.