Type Record · As of May 3, 2026
WACO CTO
Fixed Wing Single Engine · JACOBS L4 /R755-7
Registered
17
Year Range
1929–1941
NTSB Events
7
Airworthiness Directives
0
01 / Distribution
Where the fleet lives and was built
Counts of currently-registered WACO CTO aircraft by US state and decade of manufacture, sourced from the FAA Aircraft Registry.
By State (top 10)
- MT 17.6% 3
- DE 11.8% 2
- FL 11.8% 2
- CA 11.8% 2
- WI 11.8% 2
- MO 5.9% 1
- IL 5.9% 1
- TN 5.9% 1
- WY 5.9% 1
- TX 5.9% 1
+1 more states
By Decade of Manufacture
- 1920s 35.3% 6
- 1930s 29.4% 5
- 1940s 5.9% 1
- Unknown 29.4% 5
02 / NTSB Records
Events involving WACO CTO aircraft
7 event(s) on file. Showing the most recent 7.
-
Mar 29, 2016
N744HRidgeland, South Carolina
NTSB Docket → -
Feb 25, 2008
N845VVenice, Florida Minor
NTSB Docket → -
Aug 7, 2005
N7446Shelbyville, Illinois
NTSB Docket → -
Oct 7, 2003
N9577HGreenfield, Indiana
NTSB Docket → -
Aug 28, 1990
N613NKEENE, New Hampshire
NTSB Docket → -
Jan 23, 1982
N8584HOBBS, New Mexico
NTSB Docket → -
May 14, 1970
N845VMT.VERNON, Washington
NTSB Docket →
02c / Academic Research
Scholarly work mentioning WACO CTO
Papers and reports across NASA, NTSB, FAA CAMI, AOPA ASI, Embry-Riddle, arXiv, and the broader academic graph that mention this airframe. Title or keyword match — drill into each for full abstract + author list + PDF link.
- arXiv 2026 · arXiv preprint
Trajectory Optimization of Morphing Aerial Vehicles Based on Mid-Fidelity Aeroservoelastic Models
Morphing aerial vehicles offer enhanced maneuverability and fuel efficiency compared to fixed-wing configurations. However, the trade-off between performance gains and control cost in dynamic, unstead…
- arXiv 2026 · arXiv preprint
Geometric Trajectory Optimization for TRACON Arrivals: An NLP Approach with ATC Vectoring Maneuver Modeling
Terminal airspace congestion remains a major bottleneck in the global air traffic network. Although the Aircraft Sequencing and Scheduling Problem (ASSP) has been widely studied, many methods rely on …
- arXiv 2026 · arXiv preprint
Trajectory-Based Optimization for Air Traffic Control in the Terminal Maneuvering Area
We present a trajectory-based optimization framework for arrival sequencing and scheduling in the terminal maneuvering area (TMA).
- arXiv 2026 · arXiv preprint
Trajectory Tracking Control Design for Autonomous Helicopters with Guaranteed Error Bounds
This paper presents a systematic framework for computing formally guaranteed trajectory tracking error bounds for autonomous helicopters based on Robust Positive Invariant (RPI) sets.
- arXiv 2026 · arXiv preprint
Beyond Average-Channel-Based Rate Approximations: UAV Trajectory and Scheduling Optimization With Expected Rate Consideration
This paper investigates the joint optimization of trajectory, user scheduling, and time-slot duration in unmanned aerial vehicle (UAV)-assisted wireless communication systems under minimum expected sp…
- arXiv 2026 · arXiv preprint
X-VORTEX: Spatio-Temporal Contrastive Learning for Wake Vortex Trajectory Forecasting
Wake vortices are strong, coherent air turbulences created by aircraft, and they pose a major safety and capacity challenge for air traffic management.
Browse the full corpus — academia portal ↗
03 / Airworthiness Directives
FAA directives applicable to WACO CTO
No matching airworthiness directives are on file for this make and model in the Federal Register.
04 / Type Certificate Data Sheets
FAA TCDS for WACO CTO
The TCDS is the legal certification document — weight limits, performance, equipment, AD compliance times, operating limitations. 1 match in the FAA catalog.
- ATC 257 Current Rev 0 ·
The Waco Aircraft Company
Models: CTO
06 / Supplemental Type Certificates
Modifications approved for WACO CTO
11 STCs on file — every FAA-approved modification, alteration, or installation for this aircraft. STOL kits, avionics, fuel systems, floats, engine swaps, you name it.
-
05/17/2024
STC SA4503NM (PAGE 2)
Remove original cloth covering and install Ceconite covering
Ceconite Division of Poly-Fiber Inc.
-
05/19/2022
STC SA04776NY (1 OF 2)
The HIPEC Covering and Finishing System must be performed and maintained
HIPEC Aircraft Coatings Inc.
-
12/20/2017
STC SA01406NY
Installation of Airwolf remote mounted engine oil filter kit AFC-K017 on single and multi-engine fixed light aircraft and\nrotary wing
Airwolf Filter Corporation
-
08/27/2016
STC SA01240SE (5 OF 5)
Installation of secondary voltage indication system
Visual Instruments LLC
-
10/31/2012
STC SA01406NY
Installation of Airwolf remote mounted engine oil filter kit AFC-K017 on single and multi-engine fixed light aircraft and\nrotary wing
Airwolf Filter Corporation
-
02/25/2011
STC SA4503NM (PAGE 2)
Install Ceconite covering material.
Ceconite Division of Poly-Fiber Inc
-
06/26/2009
STC SA01734SE (PG 4)
Application of Stewart Systems synthetic fabric covering system to aircraft fuselage, wings, tail surfaces, control surfaces and related parts.
Stewart Thomas D. and Stewart Dan R.
-
07/24/2008
STC SA02033AT (PAGE 5)
Modification to install an air-oil separator to prevent oil from being aspirated from the engine breather line (47J series w stc's SH4-235SW, SH4-826SW or SH479SW)
M-20 Oil Separators LLC
-
04/02/2006
STC SA01240SE (5 OF 5)
Installation of secondary voltage indication system
Visual Instruments LLC
-
03/29/2006
STC SA02268CH (PAGE 5)
Installation of Airwolf Filter Corp. Air Oil Separator
Airwolf Filter Corporation
-
10/13/1989
STC SA4302NM (PAGE 2)
Installation of Electronics Int'l digital automatic engine analyzer.
Electronics International
04 / Regulations watching this type
Advisory Circulars and Federal Register activity for WACO CTO
Advisory Circulars
No ACs explicitly mention this type. Showing universal operating-rule ACs that apply to all aircraft.
Recent Federal Register activity
Latest rulemakings touching general operating rules (Part 91) and maintenance rules (Part 43).
- 2026-04-17 Settlement Policy for Small Unmanned Aircraft System (UAS) Cases FR ↗
- 2026-02-10 Normalizing Unmanned Aircraft Systems Beyond Visual Line of Sight Operations; Reopening of Comment Period; Denial of Extension FR ↗
- 2026-02-02 25-Hour Cockpit Voice Recorder (CVR) Requirement, New Aircraft Production FR ↗
- 2026-01-28 Normalizing Unmanned Aircraft Systems Beyond Visual Line of Sight Operations; Reopening of Comment Period FR ↗
- 2026-01-07 Requirements for Interference-Tolerant Radio Altimeter Systems FR ↗
05 / Aircraft of this type
All 17 registered N-numbers
Every tail currently on the FAA registry for this make/model. Click an N-number to query the FAA Aircraft Inquiry; rows flagged ● have NTSB events on file. Tails seeded with full TallyAero pages link directly.
| N-number | St | Year | NTSB | FAA |
|---|---|---|---|---|
| N21R | DE | 1929 | · | Look up ↗ |
| N280W | MO | 1932 | · | Look up ↗ |
| N29TW | MT | — | · | Look up ↗ |
| N515M | IL | — | · | Look up ↗ |
| N610N | FL | 1929 | · | Look up ↗ |
| N613N | TN | 1929 | ● | Look up ↗ |
| N655N | MT | 1930 | · | Look up ↗ |
| N657N | WY | 1929 | · | Look up ↗ |
| N666N | MT | 1930 | · | Look up ↗ |
| N7446 | CA | — | ● | Look up ↗ |
| N744H | TX | — | ● | Look up ↗ |
| N763K | DE | 1941 | · | Look up ↗ |
| N844V | FL | 1930 | · | Look up ↗ |
| N845V | WI | 1930 | ● | Look up ↗ |
| N8584 | WI | — | ● | Look up ↗ |
| N949H | CA | 1929 | · | Look up ↗ |
| N9577H | IN | 1929 | ● | Look up ↗ |
Source — FAA Aircraft Registry · click "Look up" to query the live registry record (owner, address, last airworthiness)
05 / Sources & Methodology
Every count traces back to a primary US-government source
- FAA Aircraft Registry →
Refreshed Apr 27, 2026
Available
- NTSB CAROL →
Refreshed Apr 27, 2026
Available
- Federal Register (FAA Airworthiness Directives) →
Refreshed Apr 27, 2026
Available
We render counts and lists as the agency publishes them. Read the methodology →