Cessna 172 Type Certificate Data Sheet (TCDS 3A12)

What Is a Type Certificate Data Sheet?

A Type Certificate Data Sheet (TCDS) is an official FAA document that defines the approved airworthiness standards for a specific aircraft type. It is part of the aircraft's type certificate — the FAA's approval of the aircraft design. The TCDS specifies approved engine options, weight limits, CG envelope, airspeed limitations, fuel types, and more for each model variant covered under the certificate.

When a question arises about whether a particular configuration is airworthy — what engine can be installed, what the maximum gross weight is, what fuel types are approved — the TCDS is the authoritative reference.

Engine Options by Model

Weight and CG Limits

• Maximum gross weight: 2,300–2,550 lbs depending on model variant
• CG range: approximately 35–47.3 inches aft of datum (varies by model and fuel/loading configuration)
• Datum: leading edge of the firewall (check specific model for exact datum location)

Airspeed Limitations (Typical)

Note: Exact values vary by model year and serial number. Always reference the specific aircraft's POH for operating limitations.

Fuel Types Approved

The Cessna 172 TCDS specifies approved fuel grades. Most models approve:

• 100LL (Avgas) — the standard at most GA airports, blue in color
• 100/130 grade — approved on older models with higher-compression engines
• 91UL — unleaded avgas approved for some IO-360 variants; check specific STC or TCDS notes
• Mogas (automotive gasoline) — only with an approved STC; not approved under the base TCDS

For student pilots preparing for oral exams: "What fuel does this aircraft require?" is a standard DPE question. The answer comes from the TCDS and the POH Limitations section — both are valid references.

Using the TCDS for Checkride Preparation

DPEs expect Private Pilot and Commercial Pilot applicants to know where aircraft limitations come from and how to find them. Common checkride oral questions related to the TCDS include:

• "Where do you find the maximum gross weight for this aircraft?" — POH Limitations section (derived from TCDS)
• "What engine is approved in this airplane?" — TCDS or the POH equipment list
• "Can you install a different propeller?" — Only if listed in the TCDS or covered by an STC on file with the aircraft
• "What's the never-exceed speed?" — Vne is in the POH Limitations; the TCDS is the authoritative source behind that number

Students preparing for their Instrument Rating or commercial checkride should be comfortable locating the TCDS on the FAA's rgl.faa.gov website and cross-referencing it with their aircraft documentation. Examiners view familiarity with the TCDS as a sign that a pilot understands the regulatory basis of airworthiness — not just the operating numbers.

Why Pilots Reference the TCDS

• Weight & balance calculations — TCDS confirms the datum reference and CG envelope
• Engine/propeller substitution — only engines and propellers listed in the TCDS (or an STC) are approved
• Maintenance decisions — TCDS specifies required inspections and compliance notes
• Oral exam preparation — DPEs may ask where to find gross weight limits; the TCDS and POH are both valid answers