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N4521KCessna 172S SkyhawkActive

Cessna 172S SkyhawkOwned

Rank 1 of 4 by operating margin

Jul 1, 2026 – Sep 30, 2026

2026-07-01 to 2026-09-30

Revenue

$44,289

−29%vs. previous period

Hours flown

239.4

−30%vs. previous period

Revenue/hr

$185

0%vs. previous period

Utilization

26.8%

−12 ptsvs. previous period

Monthly performance

Apr–Sep, by calendar month.

Upcoming inspections

Maintenance

Due date	Item	Hours / interval	Status
Nov 5, 2026est	Next 100-hour	76.7 hours to go 23% of the way	In 36 days
Dec 31, 2026	Next annual	12 calendar months 76% of the way	In 92 days
April 2028est	Overhaul	790.0 hours to the 2,000-hour TBO 61% of the way	In 549 days

Due date

Item

Hours / interval

Status

Nov 5, 2026est

Next 100-hour

76.7 hours to go

23% of the way

In 36 days

Dec 31, 2026

Next annual

12 calendar months

76% of the way

In 92 days

April 2028est

Overhaul

790.0 hours to the 2,000-hour TBO

61% of the way

In 549 days

Aircraft information

Make / model: Cessna 172S Skyhawk
Ownership: Owned
Engine TBO: 2,000 hrs
Engine hours since overhaul (SMOH): 1,210 hrs (entered Aug 31, 2026)
Current tach: 6351.2
Overhaul cost: $42,000
Hourly rate: $185/hr
Fuel burn: Not set

What the numbers show

Operating margin fell compared with the previous period, mostly on N4521K.

N4521K−$13,186 est

It went from $54,320 to $41,134; the largest part was fewer hours flown.

Ideas schools in this spot often explore

What changed in demand: student starts, renters, weather, or aircraft availability.
The bills behind the cost line that moved most, and whether they're one-off.
Which months in the period drove the change, and whether it repeats each year.

Ideas, not recommendations. Your situation may differ.

Show the numbers

The fleet's operating margin was $41,134, down $13,186 from $54,320 in the previous period (Apr–Jun 2026); N4521K accounts for $11,007 of that change.

Operating margin: $41,134

Previous period: $54,320

N4521K change: -$11,007

Operating margin: $41,134

Previous period: $54,320

N4521K change: -$11,007

Facts from your data, not a diagnosis.

Flew 100.6 fewer hours (239.4 vs 340), costing $9,842. main factor
Hours flown: 239.4 h
Hours flown, previous period: 340.0 h
Hours effect: -$9,842
Maintenance cost per hour rose from $19.25 to $30.61, costing $2,721. smaller factor
Maintenance per hour: $30.61/hr
Maintenance per hour, previous period: $19.25/hr
Maintenance effect: -$2,721
Fuel cost per hour fell from $59.66 to $50.46, adding $2,202. smaller factor
Fuel per hour: $50.46/hr
Fuel per hour, previous period: $59.66/hr
Fuel effect: $2,202
Other changes: −$646. smaller factor
Other changes: -$646
Total change: -$11,007

Cancellations are costing N4521K real flying time.

N4521K$6,660 est Scheduled value of cancelled hours

10% of bookings were cancelled or no-shows, 36.0 scheduled hours worth about $6,660 at the usual rate.

Ideas schools in this spot often explore

Whether the day most cancellations fall on has something in common: weather patterns, instructor rosters, or a recurring group of students.
What's different about the bookings of the instructor on most of them: students, times, or workload.
How the cancellation and no-show policy is set: notice period, fees, and whether it's applied consistently.

Ideas, not recommendations. Your situation may differ.

Show the numbers

N4521K had 18 cancelled or no-show bookings (10% of its 189 bookings) covering 36.0 scheduled hours; its revenue per hour was $185.00.

Cancelled or no-show bookings: 18

Cancellation rate: 10%

Scheduled hours: 36.0 h

Revenue per hour: $185.00/hr

Cancelled or no-show bookings: 18

Cancellation rate: 10%

Scheduled hours: 36.0 h

Revenue per hour: $185.00/hr

Facts from your data, not a diagnosis.

7 of the 18 cancelled or no-show bookings fell on a Saturday. smaller factor
On Saturdays: 7
Cancelled or no-show bookings: 18
One instructor was on 5 of the 12 cancelled or no-show bookings that name an instructor. smaller factor
With the same instructor: 5
Naming an instructor: 12
17 of the 18 cancelled or no-show bookings that name a customer were booked again by the same customer within 7 days. main factor
Booked again: 17
Naming a customer: 18
Rebooked share: 94%

N4521K's next inspection falls in the same two weeks as other aircraft's.

N4521K

N4521K flew 48% of the fleet's hours, and the others are due within days of it, so they could all be down at once.

Ideas schools in this spot often explore

Bringing one inspection forward a few days so the aircraft aren't down at the same time.
Whether the shop can take two aircraft in the same week, and how long each would take.
Which bookings fall in those weeks and could move to other aircraft.

Ideas, not recommendations. Your situation may differ.

Show the numbers

N4521K's 100-hour (about Nov 5, 2026) falls within 14 days of N8123V's 100-hour (about Oct 27, 2026) and N744PS's 100-hour (about Oct 28, 2026) (projected). N4521K flew 48% of the fleet's hours from 2026-07-03 to 2026-09-30.

N4521K 100-hour: about Nov 5, 2026

Also due: N8123V 100-hour: about Oct 27, 2026

Also due: N744PS 100-hour: about Oct 28, 2026

N4521K share of fleet hours: 48%

N4521K 100-hour: about Nov 5, 2026

Also due: N8123V 100-hour: about Oct 27, 2026

Also due: N744PS 100-hour: about Oct 28, 2026

N4521K share of fleet hours: 48%

Facts from your data, not a diagnosis.

N4521K: 100-hour (about Nov 5, 2026); it flies about 46.4 tach hours a month, and flew 48% of the fleet's hours from 2026-07-03 to 2026-09-30. main factor
N4521K hours per month: 46.4 h/month
N4521K share of fleet hours: 48%
Also due within 14 days: N8123V's 100-hour (about Oct 27, 2026) and N744PS's 100-hour (about Oct 28, 2026). smaller factor
Other aircraft due in the same weeks: 2

est Includes estimated values: inferred bills, placeholder fixed costs or allocated fuel. Figures for cancellations, downtime and unbilled ground sessions are estimates by design.

Utilization by month

Apr–Sep, by calendar month. Based on your weekly schedule.

Flights, newest first

Date	Kind	Hobbs start	Hobbs end	Tach start	Tach end	Source
2026-08-31	rental	7483.5	7484.7	6350.2	6351.2	gsheets
2026-08-31	dual	7481.8	7483.5	6348.8	6350.2	gsheets
2026-08-31	dual	7480.0	7481.8	6347.3	6348.8	gsheets
2026-08-30	dual	7478.9	7480.0	6346.4	6347.3	gsheets
2026-08-30	rental	7477.9	7478.9	6345.6	6346.4	gsheets
2026-08-29	solo	7476.9	7477.9	6344.8	6345.6	gsheets
2026-08-29	solo	7475.4	7476.9	6343.5	6344.8	gsheets
2026-08-29	cancelled	—	—	—	—	gsheets
2026-08-29	dual	7473.5	7475.4	6341.9	6343.5	gsheets
2026-08-28	dual	7472.1	7473.5	6340.7	6341.9	gsheets
2026-08-28	solo	7470.8	7472.1	6339.6	6340.7	gsheets
2026-08-28	rental	7469.8	7470.8	6338.8	6339.6	gsheets
2026-08-28	rental	7468.7	7469.8	6337.9	6338.8	gsheets
2026-08-27	rental	7467.7	7468.7	6337.1	6337.9	gsheets
2026-08-27	solo	7466.8	7467.7	6336.3	6337.1	gsheets
2026-08-27	dual	7465.5	7466.8	6335.2	6336.3	gsheets
2026-08-26	dual	7463.8	7465.5	6333.8	6335.2	gsheets
2026-08-26	rental	7462.5	7463.8	6332.7	6333.8	gsheets
2026-08-26	solo	7461.4	7462.5	6331.8	6332.7	gsheets
2026-08-25	solo	7459.8	7461.4	6330.5	6331.8	gsheets
2026-08-25	rental	7458.3	7459.8	6329.2	6330.5	gsheets
2026-08-25	rental	7456.8	7458.3	6327.9	6329.2	gsheets
2026-08-23	maintenance	—	—	—	—	gsheets
2026-08-22	dual	7455.7	7456.8	6327.0	6327.9	gsheets
2026-08-22	no show	—	—	—	—	gsheets

Maintenance

Maintenance/hr (12-month) $25/hr

Hourly (100-hour inspections, oil, other flying wear) $22/hr

Calendar (annual and other date-driven items) $238/month

Unscheduled repairs in this range $0

Engine reserve per hour (overhaul cost ÷ TBO) $21/hr

Maintenance booked in this range $7,328

Per-hour and per-month figures cover 2025-10-01 to 2026-09-30 (995.1 Hobbs hours), so one month's annual or a month with few hours doesn't swing them. The operating break-even uses them too. Operating cost and margin stay as booked.

Largest in this range

Date	Category	Amount	Memo
2026-08-23	Hourly	$2,365	100-hour inspection N4521K
2026-07-27	Hourly	$1,950	100-hour inspection N4521K
2026-07-02	Hourly	$1,941	100-hour inspection N4521K

Coming up

Next 100-hour

About Nov 5, 2026 (at tach 6,427.9)

23% of the way

est

Next annual

Due by Dec 31, 2026

76% of the way

Overhaul

About April 2028

61% of the way

est

Reserve per hour

$21.00 needed

Dates marked est are estimates: the 100-hour from this aircraft's upcoming bookings and its last 90 days of hours (hover it for how), the overhaul projected at about 46.4 tach hours a month, month by month as it flew from 2025-10-01 to 2026-09-30, × 0.67 for its recent trend.

Maintenance downtime

Maintenance2026-07-02 08:00
Back in service2026-07-02 17:00
Maintenance2026-07-27 08:00
Back in service2026-07-27 17:00
Maintenance2026-08-23 08:00
Back in service2026-08-23 17:00

Downtime counted against utilization in this range: 27.0 h (times in America/Chicago).

Summary

Hours flown	Utilization Based on your weekly schedule.	Revenue	Operating cost	Operating margin	Loan payments	After loan payments Cash view: includes loan principal	Cost/hr	Cost/hr (12-month)
239.4	26.8%	$44,289	−$22,034est	$22,255est	−$3,450est	$18,805est	$92est	$94est

Hours flown

Utilization

Based on your weekly schedule.

Revenue

Operating cost

Operating margin

Loan payments

After loan payments

Cash view: includes loan principal

Cost/hr

Cost/hr (12-month)

239.4

26.8%

$44,289

−$22,034est

$22,255est

−$3,450est

$18,805est

$92est

$94est

Operating cost by category

Fuel	−$12,081est	55%
Maintenance	−$7,328	33%
Insurance	−$1,275est	6%
Hangar	−$1,350est	6%
Lease payment	$0	0%
Instructor pay	$0	0%
Other	$0	0%
Operating cost	−$22,034est	100%
Loan payments (after the operating margin, not in cost)	−$3,450est

est Includes estimated values: inferred bills, placeholder fixed costs or allocated fuel.

Bars are drawn against the largest category; striped bars include estimates. The percent is each category's share of the operating cost.

Fuel includes $4,084 allocated to this aircraft from fuel with no tail number, split by Hobbs hours each month (an estimate).

Fixed-cost placeholders (no bill booked that month, so the aircraft's monthly field is used): 2026-09 Insurance $4252026-09 Hangar $450

Loan-payment placeholders (no bill booked that month, so the aircraft's monthly field is used): 2026-09 Loan payment $1,150

By month

Month	Hours flown	Utilization Based on your weekly schedule.	Revenue	Operating cost	Operating margin	After loan payments Cash view: includes loan principal
July 2026	124.1	42.5%	$22,959	−$11,272est	$11,686est	$10,536est
August 2026	115.3	38.3%	$21,331	−$9,887est	$11,444est	$10,294est
September 2026	0.0	0.0%	$0	−$875est	−$875est	−$2,025est
Range total	239.4	26.8%	$44,289	−$22,034est	$22,255est	$18,805est

Cost per hour, month by month

Month	Hours	Fuel	Maintenance
Oct 2025	90.2	$67/hr	$24/hr
Nov 2025	61.1	$71/hr	$3/hr
Dec 2025	63.2	$46/hr	$45/hr
Jan 2026	56	$50/hr	$47/hr
Feb 2026	52.3	$69/hr	$4/hr
Mar 2026	92.9	$68/hr	$31/hr
Apr 2026	103.3	$58/hr	$19/hr
May 2026	111.1	$71/hr	$21/hr
Jun 2026	125.6	$51/hr	$18/hr
Jul 2026	124.1	$47/hr	$36/hr
Aug 2026	115.3	$54/hr	$24/hr
Sep 2026	0	—	—

Month

Hours

Fuel

Maintenance

Oct 2025

90.2

$67/hr

$24/hr

Nov 2025

61.1

$71/hr

$3/hr

Dec 2025

63.2

$46/hr

$45/hr

Jan 2026

$50/hr

$47/hr

Feb 2026

52.3

$69/hr

$4/hr

Mar 2026

92.9

$68/hr

$31/hr

Apr 2026

103.3

$58/hr

$19/hr

May 2026

111.1

$71/hr

$21/hr

Jun 2026

125.6

$51/hr

$18/hr

Jul 2026

124.1

$47/hr

$36/hr

Aug 2026

115.3

$54/hr

$24/hr

Sep 2026

—

Calendar maintenance (annual inspections and other dated items): 2024 (part) $3,086 · 2025 $2,862 · 2026 (part) $0

Maintenance per hour is lumpy month to month (an annual lands in one month); the 12-month rate above smooths it.

Break-even and cancellations

Break-even: 9.8 hours a month to cover $1,107 of fixed costs; it flew 79.2 a month. est
Cancelled or no-show: 10% of 189 bookings (10 cancelled, 8 no-shows).

Transactions, newest first

Date	Category	Amount	Document	Memo	Source	Match
2026-08-31	Flight revenue	$333	standard	N4521K 1.8 hobbs (dual)	quickbooks	matched
2026-08-31	Flight revenue	$315	standard	N4521K 1.7 hobbs (dual)	quickbooks	matched
2026-08-31	Fuel	−$269	standard	Fuel N4521K week ending 2026-08-31	quickbooks	matched
2026-08-31	Flight revenue	$222	standard	N4521K 1.2 hobbs (rental)	quickbooks	matched
2026-08-30	Flight revenue	$185	standard	N4521K 1.0 hobbs (rental)	quickbooks	matched
2026-08-30	Flight revenue	$204	standard	N4521K 1.1 hobbs (dual)	quickbooks	matched
2026-08-29	Flight revenue	$352	standard	N4521K 1.9 hobbs (dual)	quickbooks	matched
2026-08-29	Flight revenue	$278	standard	N4521K 1.5 hobbs (solo)	quickbooks	matched
2026-08-29	Flight revenue	$185	standard	N4521K 1.0 hobbs (solo)	quickbooks	matched
2026-08-28	Flight revenue	$185	standard	N4521K 1.0 hobbs (rental)	quickbooks	matched
2026-08-28	Flight revenue	$204	standard	N4521K 1.1 hobbs (rental)	quickbooks	matched
2026-08-28	Flight revenue	$259	standard	N4521K 1.4 hobbs (dual)	quickbooks	matched
2026-08-28	Flight revenue	$241	standard	N4521K 1.3 hobbs (solo)	quickbooks	matched
2026-08-27	Flight revenue	$241	standard	N4521K 1.3 hobbs (dual)	quickbooks	matched
2026-08-27	Flight revenue	$185	standard	N4521K 1.0 hobbs (rental)	quickbooks	matched
2026-08-27	Flight revenue	$167	standard	N4521K 0.9 hobbs (solo)	quickbooks	matched
2026-08-26	Flight revenue	$204	standard	N4521K 1.1 hobbs (solo)	quickbooks	matched
2026-08-26	Flight revenue	$241	standard	N4521K 1.3 hobbs (rental)	quickbooks	matched
2026-08-26	Flight revenue	$315	standard	N4521K 1.7 hobbs (dual)	quickbooks	matched
2026-08-25	Flight revenue	$278	standard	N4521K 1.5 hobbs (rental)	quickbooks	matched
2026-08-25	Flight revenue	$296	standard	N4521K 1.6 hobbs (solo)	quickbooks	matched
2026-08-25	Flight revenue	$278	standard	N4521K 1.5 hobbs (rental)	quickbooks	matched
2026-08-23	Fuel	−$1,208	standard	Fuel N4521K week ending 2026-08-23	quickbooks	matched
2026-08-23	Maintenance	−$2,365	standard	100-hour inspection N4521K	quickbooks	matched
2026-08-22	Maintenance	−$222	standard	Oil change N4521K	quickbooks	matched

Date