Ownership guide
Cessna 421B
220 registered in the US, built from about 1970 to 1975, 8 seats, most with the Continental GTSIO-520. Its Airworthiness Directives, its engines', and what to check before buying one.
The fleet
- Registered in the US
- 220
- Built
- 1970 to 1975
- Half built by
- 1974
- Seats
- 8
- Engine type
- Piston
- Most common engine
- Continental GTSIO-520
Engines installed
- Continental GTSIO-520191 aircraft (87%) · 18 ADs, 1 with a repeat action
- Continental TSIO-5208 aircraft (4%) · 45 ADs, 3 with a repeat action
From the FAA aircraft registry, rebuilt daily. Years are those recorded on each registration.
Airworthiness Directives
23 current ADs name the 421B airframe, 1 with a repeat action; 3 more were superseded. Its engines carry 63 more. 11 equipment ADs name the model.
The ones that come back
ADs with a repeat action: an inspection or replacement at an interval, for as long as the AD applies. These are the airworthiness costs an owner keeps paying.
What gets reported
8 Service Difficulty Reports since 2016: a mechanic or operator files one when a part fails or is found defective.
Systems reported most
- Magneto/Distributor2
- Flight Compartment Equipment1
- Reciprocating Engine Cylinder Section1
- Reciprocating Engine Rear Section1
- Ignition Harness (Distribution)1
- Fuselage, Door Hinge1
Parts reported most
- Pivot, broken1
- Piston, cracked1
- Magneto, defective1
- Support, loose1
- Magneto, faulty1
- None, failed1
The latest reports
2022-07-14 · Magneto/Distributor · Magneto, defective
Loss of 5 inches of mp at fl 240 and inflight investigation showed a rough running rh magneto. discovery of a defective spark plug lead (see other sdr) on a 25 hr ttsn champion spark plug harness led with 25 hrs ttsn spark champion rhb32e spark plugs led us to investigation of the associated magneto. during inspection of the blue label 25 hr ttsn (cmi remanufactured) s-1200 magneto we found a l
2022-06-24 · Ignition Harness (Distribution) · None, failed
Cruise flight fl 240, 25 hrs since new champion ignition harness, blue label tcm/cat bendix s6ln-1205 magneto, and champion rhb32e spark plugs at engine overhaul (25 hrs ttsmoh of engine). in cruise flight lost 5 inches of mp pressure on newly overhauled rh engine. in flight trouble shooting revealed marked engine roughness when operating only on rh mag. post flight inspection revealed evidenc
2020-09-16 · Wing, Plate/Skin · Skin, cracked
A crack on the skin at the right wing rear spar and trailing edge. the location is at the main fuel tank rear spar attach point. the crack is caused by vibration or loose rear main fuel tank attach bolt. recommended at each annual inspection, inspect the area for cracks in the skin and loose rear main fuel tank attach bolt if left, vibration might cause rear spar and main fuel tank separation a
2019-12-10 · Fuselage, Door Hinge · Hinge, corroded
Performed repair work on the aircraft for low cabin differential/pressurization. found many leaks and repaired. differential was repaired to book values. customer took possession of the aircraft and after several flight hours heard a pop and lost some pressurization in the cabin. found aft upper door hinge corroded and broken and door slightly protruding from the closed position. forward hinge mou
From the FAA's Service Difficulty Reporting System, refreshed monthly. Counts of what was reported, not failure rates: most of general aviation reports voluntarily, and a busy training fleet reports more than a private one.
Accident record
19 accidents since 2008, 5 fatal (15 people killed in them, a midair counting both aircraft), 2 aircraft destroyed.
What happened
- Fuel starvation3
- Landing gear collapse2
- Loss of engine power (total)2
- Runway excursion2
- Fuel exhaustion1
- Fire/smoke (non-impact)1
Phase of flight
- Initial climb6
- Takeoff4
- Landing3
- Approach3
- Enroute1
The latest
| Date | Where | What happened | Injuries | NTSB number |
|---|---|---|---|---|
| 2026-03-27 | Sedona, AZ | Landing: Landing gear collapse | None | WPR26LA145 |
| 2022-07-16 | Riverdale, NE | Approach: Fuel starvation | Minor | CEN22LA341 |
| 2021-01-10 | Old bethpage, NY | Initial climb: Fuel exhaustion | Serious | ERA21LA098 |
| 2018-06-05 | Rock sound | Initial climb: Fire/smoke (non-impact) | Fatal | ERA18WA159 |
| 2017-06-22 | Carlsbad, CA | Landing: Landing gear collapse | None | WPR17LA131 |
| 2015-10-14 | Hammond, LA | Initial climb: Loss of engine power (total) | Fatal | CEN16FA013 |
From the NTSB's aviation accident database, refreshed monthly; accidents only, homebuilts left out. Counts, not rates: nobody publishes how many hours each model flies, and a training fleet flies far more than a private one. Look up any case by its number in the NTSB's CAROL.
What it costs to run
Per hour flown
Per year, flown or not
- Fuel
- $0/hr
- Engine reserve
- $0/hr
- A year
- $0
- All in, per hour
- $0/hr
Everything else is yours to fill in: insurance, hangar and overhaul prices vary too much by pilot, airport and shop for a default to mean anything. Nothing you type leaves this page.
Before you buy one
- Run its N-number through the AD check: every AD that names its airframe and engine, as a checklist to take to the logbooks.
- For each repeat-action AD (1 on the airframe), find the last compliance in the logbooks and when the next one is due.
- Compare the engine's time since overhaul with its maker's published overhaul time, and look for the reason behind any long gap in flying.
- Ask the mechanic doing the pre-buy to look hard at the magneto/distributor and for broken pivots: they are what gets reported most on this model.
- 11 equipment ADs name the 421B (a muffler, a seat belt, a display): find out which of that equipment is installed.
- Check the registration, the airworthiness certificate and the date of the last annual inspection.
- Work out the sales or use tax your state will charge with the aircraft tax calculator.
The rest of the 421 family
Questions
- How many Cessna 421Bs are registered in the US?
- 220, in the FAA aircraft registry.
- When was the Cessna 421B built?
- From about 1970 to 1975. Half of those registered today were built by 1974.
- What engine does the Cessna 421B have?
- Most have the Continental GTSIO-520 (87% of those registered); others have the Continental TSIO-520.
- What are common problems with the Cessna 421B?
- In 8 Service Difficulty Reports filed with the FAA since 2016, the systems reported most were magneto/distributor, flight compartment equipment, reciprocating engine cylinder section, and the part most often reported was a broken pivot.
- How many accidents has the Cessna 421B had?
- 19 in the NTSB's database since 2008, 5 of them fatal. The most common defining event was fuel starvation. These are counts, not rates: how many hours the fleet flew is not published.
- How many Airworthiness Directives does the Cessna 421B have?
- 23 current ADs name the 421B airframe, 1 of them with a repeat action, and 63 more name its engines. Whether each applies to one aircraft depends on its serial number and installed equipment.
Figures from the FAA aircraft registry and the FAA's Airworthiness Directives, rebuilt daily. An AD listed for a model is one to read; whether it applies to one aircraft depends on its serial number, equipment and records.