- Holder
- Pratt & Whitney Division
- Revision
- 15
- Revised
- September 6, 1967
- Status
- Current
- Product
- Engine
- Certification basis
- CAR 13
- Models
- 4
The release keeps the latest revision of each data sheet. Model names are as the data sheet lists them.
On this page
Models · 4
| Model | Also known as | Note |
|---|---|---|
| JT3C-7 | ||
| JT3C-12 | ||
| JT3C-6 | ||
| JT3C-4 |
Airworthiness directives · 9
ADs whose products are models on this data sheet, matched by model and maker.
AD 66-21-01Rotor Disc Spacer AssembliesAD 66-16-06Rotor Disc Spacer AssembliesAD 64-05-05Throttle Valve AssembliesAD 62-09-04Compressor Rotor BladesAD 56-06-02Cylinder Flange Attaching StudAD 59-10-09Turbine BladeAD 60-22-02Combustion Chamber Outer CasesAD 60-23-04GearshaftAD 62-17-06Compressor Rotor Disc
Registered aircraft
Registry models that point at this data sheet, with their registered aircraft.
STCs approved under this data sheet · 2
What the data sheet says
From the PDF’s text layer, line by line: tables lose their columns. The PDF is the record.
Page No. 1 2 3 4
Rev No. 15 15 15 15
Reformatted 11/93.
FEDERAL AVIATION ADMINISTRATION
E-290-15
PRATT & WHITNEY
Turbo Wasp
JT3C-4
JT3C-6
JT3C-7
JT3C-12
September 6, 1967
TYPE CERTIFICATE DATA SHEET NO. E-290
Engines of models described herein conforming with this data sheet (which is a part of type certificate No. 290) and other approved data
on file with the Federal Aviation Administration meet the minimum standards for use in certificated aircraft in accordance with pertinent
aircraft data sheets and applicable portions of the Civil Air Regulations provided they are installed, operated, and maintained as
prescribed by the approved manufacturer's manuals and other approved instructions.
Manufacturer Pratt & Whitney Aircraft
Division of United Aircraft Corporation
East Hartford, Connecticut
Model Turbo Wasp JT3C-4 JT3C-6 JT3C-7 JT3C-12
Type Turbojet, Dual Axial, - - - - - -
16 stage compressor, 3
stage turbine and 8
cannular combustion
chambers
Ratings (See NOTE 11)
Maximum continuous static thrust
at sea level, lb. 9500 10,000 10,000 11,500
Takeoff static thrust at sea level, lb.
dry (5 minutes) 11,200 11,200 12,000 13,000
with water injection (2-1/2 minutes) 12,500 13,500 - -
Fuel control Hamilton JFC-12 - - Hamilton JFC-25 - -
Fuel See Note 14 - - - - - -
Fuel pump Chandler Evans 9400 two- - - Chandler Evans 9430 - -
stage
Air bleed governor Holley A 12110 - - Holley A 12115 - -
Oil (See Note 15) Synthetic type conforming - - - - - -
to P&WA 521 as revised.
Principal Dimensions:
Length, In. (maximum including front-
mounted compressor bleed control) 138.97 - - 137.38 - -
Width 38.9 - - - - - -
Height 46.7 - - - - - -
Weight (dry), lb. (includes basic engine
with all essential access., but excluding
starter, exhaust nozzle, power source
for the ignition system, and oil supply
tank) 4234 - - 3495 3550
Center of gravity, in.
Aft of front mount area center line 18.34 - - 20.27 20.30
Below engine center line 1.20 - - - - 1.43
Ignition GLA 18200-11 with two
spark igniters: Champion
AA-15S, AA-35S, AA-37S
or AA-72S; BG 12625;
AC JB-57, JC-571 or JB-3
- - GLA 40355B with two
spark igniters:
Champion
AA-15S, AA-35S,
AA-37S or AA-72S;
BG 12625; AC JB-57,
JC-571 or JB-3.
- -
NOTES 1 thru 14 1 thru 14 1 thru 14 1 thru 14
"- -" indicates "same as previous model"
" " indicates "not applicable"
E-290, Rev 15
Page 2
Certification basis CAR 13, effective June 15, 1956, as amended by 13-1, 13-2, and 13-3. Type Certificate
No. 290 issued March 15, 1957, for JT3C-4; JT3C-6 added June 19, 1957; JT3C-7 added
May 26, 1959; JT3C-12 added April 14, 1961.
Date of Application for Type Certificate September 18, 1956.
Production basis Production Certificate No. 2.
NOTE 1. Maximum permissible engine operating speeds for the engine rotors are as follows:
JT3C-4, -6 JT3C-7 JT3C-12
Low pressure compressor (N1) 7000 6850 - -
High pressure compressor (N2) 9950 - - 10150
NOTE 2. Maximum permissible temperatures are as follows:
Turbine outlet gas temperatures:
Takeoff (5 minutes) (630°C) 1166°F (620°C) 1148°F (665°C) 1229°F
Maximum continuous (560°C) 1040°F (540°C) 1004°F (600°C) 1112°F
Maximum for acceleration
(2 minutes) (650°C) 1202°F - - (695°C) 1283°F
Starting: ground (450°C) 842°F - - - -
air (500°C) 932°F - - - -
Oil inlet (121°C) 250°F - - (121°C) 250°F continuous
operation
(143°C) 290°F Ten (10) min.
Ground operation
only
External engine components, maximum temperature (Limiting temperature of specific components are as
specified in pertinent engine installation and operating manual or P&WA Installation Handbook.)
NOTE 3. Fuel and oil pressure limits are as follows:
Fuel pressure, at inlet to engine system pump, 7.5 p.s.i. above absolute fuel vapor pressure or 1.5 p.s.i.
below fuel tank pressure, whichever is higher, with a maximum of 55 p.s.i. above absolute ambient
atmospheric pressure.
Oil pressure
At idle, 30 p.s.i. minimum
Operating range, 40 to 50 p.s.i.
NOTE 4. Maximum permissible air bleed extraction is as follows:
Low compressor:
JT3C-4, C-6 JT3C-7 JT3C-12
1% from idle to M.C. 2.75% at idle reducing to 2.0% at M.C. 2.75% at idle reducing to 2.4% at M.C.
2.2% at takeoff speed 2.2% at takeoff speed 1.2% at takeoff speed
1.8% intermittent for thermal
anti-icing
High compressor:
JT3C-4, C-6, C-7 JT3C-12
5.5% from idle to M.C. 5.5% at idle reducing to 4.5% at
M.C.
2.0% at takeoff speed 2.4% at takeoff speed
3.1% for three-engine takeoff 3.1% for three-engine takeoff
E-290
Page 3
NOTE 5. These ratings are based upon static test stand operation under the following conditions:
Compressor inlet air at 59°F and 29.92 in.Hg.
Jet nozzle and exhaust pipe per P&WA Dwg. 279401
P&WA bellmouth on air inlet
No aircraft accessory loads or air extraction
No anti-icing airflow
Turbine outlet gas temperature limits not exceeded
At engine data plate N2 r.p.m.
NOTE 6. The following accessory drive provisions are incorporated:
Speed Ratio
Direction of to Torque (in. lb.) Overhang
Drive Rotation* Turbine Shaft Continuous Static (in. lb.)
Low Rotor
Tachometer C .679:1 7 50 -
High Rotor
Starter C .700:1 ** ** 625
Generator C .678:1 1000 4400 625
Fluid power pump*** C .355:1 1000 4400 400
Tachometer C .421:1 7 50 -
* "C" - Clockwise when viewed facing pad
** Max. starter torque 550 pound-feet. Shear section should withstand 1100 pound-feet.
*** May be used as generator drive when proper shaftgear is installed at same ratio and overhang
as other generator drive.
NOTE 7. The following optional items, when used, increase the basic engine weight as follows:
P&WA water regulator, piping and brackets.
JT3C-4 40 lb.
JT3C-6 60 lb.
P&WA engine-mounted oil tank, Part No. 315183 25 lb.
NOTE 8. For water injection operation, the following water flow rates are utilized: JT3C-4 JT3C-6
Constant water flow - lb./min. 250 667
Feed pressure - p.s.i. 150 - 225 350 - 437
Water alone is specified and should contain no more than 10 (PPM) parts per million impurities.
Use of water with appreciable mineral content will cause gradual dry power deterioration from deposits
on the compressor blades and result in the need for more frequent speed trimming and engine cleaning.
Use of water is limited to takeoff operation up to an altitude of 9,000 feet, at 11°F (minus 12°C) or
above, ambient temperature, water injection to the engine diffuser only, and at 40°F (5°C) or above,
ambient temperature, water injection to the compressor inlet and engine diffuser.
NOTE 9. Power setting, power checks, and control of engine output in all operations is to be based upon P&WA
engine charts referring to turbine discharge section gas pressures. Pressure probes are included in the
engine assembly for this reason.
NOTE 10. These engines meet FAA requirements for adequate turbine disc integrity and rotor blade containment and
do not require external armoring. These engines have demonstrated satisfactory operation in icing con-
ditions as defined in CAR 4b.1(b)7 and 8.
NOTE 11. (a) Maximum Continuous Thrust. Maximum continuous static thrust at sea level permitted as follows:
JT3C-6: At -22°F ambient temperature and below, 13,500 lb.
JT3C-7: At 41°F ambient temperature and below, 12,000 lb.
JT3C-12: At 25°F ambient temperature and below, 13,000 lb.
The pertinent engine installation and operating manual of P&WA Installation Handbook should be
consulted for variation in thrust between standard day and the ambient temperature stated above.
(b) Takeoff Thrust. Takeoff thrust (dry) permitted as follows:
E-290, Rev 15
Page 4
JT3C-6: Below 11°F inlet temperature, 13,500 lb. for 5 minutes.
JT3C-7: Below 43.5°F inlet temperature, 12,500 lb. for 5 minutes.
Takeoffs using both water injection and dry takeoff power are limited to a maximum period of 5 minutes
including operation with water injection for not more than 2 1/2 minutes.
NOTE 12. The serial number suffix "B" designates engine for the Boeing 707 aircraft and the suffix "D" designates
engines for the Douglas DC-8 aircraft. Differences in these engines involve differences in the routing
of external engine lines.
NOTE 13. The above engines incorporate the following detailed characteristics:
JT3C Model
C-4 Basic model.
C-6 Same as C-4 except for increased wet takeoff and maximum continuous ratings.
C-7 Same as C-6 except for increased dry takeoff rating, decreased weight and
no water injection.
C-12 Same as C-7 except for increased ratings with improved engine parts.
NOTE 14. JP-1, JP-4, and JP-5 fuels conforming to P&WA Specification No. 522 and later revisions may be used
separately or mixed in any proportions without adversely affecting the engine operation or power out-
put. No fuel control adjustment is required when switching fuel types.
Phillips PFA-55MB anti-icing additive at the use concentration not in excess of 0.15% volume is
approved for use in fuels conforming to P&WA Specification No. 522D.
Shell ASA-3 anti-static additive at a concentration that will provide not in excess of 300 conductivity
units, which is approximately equivalent to 1 p.p.m. in approved for use in fuels conforming to
P&WA Specification No. 522E or later revision.
NOTE 15. P&WA Turbojet Engine Service Bulletin No. 238 approved brand oils.
NOTE 16. Certain engine parts are life limited. These limits are listed in the FAA-Approved Pratt & Whitney
Aircraft JT3C-6 Turbojet Engine Overhaul Manual Part No. 363433, Fits and Clearances Section and
the FAA-Approved Pratt & Whitney Aircraft JT3C-7 and -12 Turbojet Engines - Overhaul Manual
Part No. 395954, Fits and Clearances Section.
....END....