# TCDS ATC 21 Wright: Wright Aeronautical Division Curtiss-Wright Corporation

- Type: Type certificate data sheet
- Status: Current
- Holder: Wright Aeronautical Division Curtiss-Wright Corporation
- Revision: 0
- Product: Engine
- Data sheet PDF: https://openairdocs.org/files/sha256/44/96/449683713a7f3f1249b9ef4e2b06429feb36fd5499c850d178f20dfc0aefebec
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/822FDD7BD56E5A35862572C0006DAC21.0001
- Page: https://openairdocs.org/tcds/ATC%2021%20Wright

## Models (5)

As the data sheet lists them.

- Whirlwind R-975B
- Whirlwind R-975
- Whirlwind R-975D
- Whirlwind R-975A
- Whirlwind R-975E

## What the data sheet says

This is OCR from the scanned FAA data sheet. OCR can misread letters and numbers.

```text
MODELS:  Wright Whirlwind R-975, A, B. D. E
1.C. NOMEER: AIC 21
Model - Whirlwind  R-975E
туре  - 9RA  Direct drive
rating:
Maximum continuous,
Of. Ipm, at S.L.
Fressure altitude  330-2000-S.L.
Take-off  (one minute) .
hp. rpm, at full
throttle  330-2000
Fuel  (minimum octane
aviation gasoline)  73
Fore and stroke, in.  5.0 × 5.5
[isplacement, cu. in.  972
Compression ratio  5.1:1
635
Supercharging
(imfeller gear ratio)
Carturetion  Stromberg NA-F9 or NA-R9A carburetor with 2-7/16 in. verturi
Scintilla VAG-9DF or SR-9R magnetos
Certification tasis  Approved Type Certificate No.
NOTE 1. Includes R-975, R-975A, R-975B and R-975D engines.
NCIE 2. Weight (dry) includes carburetor air heater and cleaner.
KOTE 3.  APproval expired 7/12/37  No engines of these models manufactured after this date or with serial numbers
bove 13122 (except A15053) eligitle for use in certificated aircraft
NOTE 4.  Maximum permissible cylinder head, barrel and oil inlet temperatures, 500 degrees F., 325 degrees F..
and 200 degrees F.. respectively.
```

## ADs

None name its models.

## STCs approved under this data sheet (1)

- [STC SE04651CH](https://openairdocs.org/stc/SE04651CH): To allow use of l00R grade aviation fuel meeting Swift Fuel, LLC specification SPEC-l00R-22. Swift Fuels LLC

## PMA parts (OpenAirDocs) (6)

Current parts manufacturer approvals (PMA): parts the FAA has approved companies to make as replacements or modifications. Each record lists its models as free text; OpenAirDocs matched them to this data sheet's models, so check the FAA record before relying on it. Newest first.

- [72-231114-2](https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID165594803620260722204356.0001): TAG-Engine. Swift Fuels, LLC · PMA PQ04423CE · Modification part · For Whirlwind R-975B, Whirlwind R-975, Whirlwind R-975D and 2 more · Jul 17, 2026
- [YA110001](https://drs.faa.gov/browse/excelExternalWindow/550E72ED82183C188625772D005C56DA.0001): Gasket - Rocker Cover Paper. Yesteryear Aviation Inc · PMA PQ4039CE · Replaces 110001 · For Whirlwind R-975 · May 13, 2010
- [YA110001-R](https://drs.faa.gov/browse/excelExternalWindow/53FEE8249323D8028625772D005C5706.0001): Gasket - Rocker Cover Rubber. Yesteryear Aviation Inc · PMA PQ4039CE · Replaces 110001-R · For Whirlwind R-975 · May 13, 2010
- [UREB37E URHB37E](https://drs.faa.gov/browse/excelExternalWindow/C2F2D61F0CDCC1D58525704C00570B8F.0001): Spark Plug. Slick Aircraft Products, Division of Unison Ind · Replaces SL 30A SL 300A Allied Signal (Autolite) · For Whirlwind R-975 · Jul 1, 1999
- [UREM40E URHM40E](https://drs.faa.gov/browse/excelExternalWindow/1E40C481546604768525704C00570B91.0001): Spark Plug. Slick Aircraft Products, Division of Unison Ind · Replaces SL 20A SL200A Allied Signal (Autolite) · For Whirlwind R-975 · Jul 1, 1999
- [AEI12403](https://drs.faa.gov/browse/excelExternalWindow/B6A04E3CC533315E8525703B005473DF.0001): Throttle Shaft Screw. Aero-Engines Inc · Replaces Bendix Products P-12403 · For Whirlwind R-975 · Dec 8, 1998

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.