MIL-PRF-23699 is the U.S. military performance specification for inhibited, synthetic hydrocarbon-base turbine engine lubricants. Oils qualified to this specification are 5 mm²/s synthetic hindered ester fluids formulated with additives to improve thermal and oxidation stability and metal passivation. AeroShell Turbine Oil 500, one of the most widely approved products under this specification, was developed to meet the requirements of Pratt & Whitney 521 Type II and MIL-PRF-23699 and is approved as an SAE AS5780B Grade SPC (Standard Performance Capability) oil. These oils are not compatible with all seal materials and should not be used in contact with incompatible elastomers; refer to manufacturer guidance before use.
MIL-PRF-23699 as a Turbine Engine Lubricant
Specifications
| Authority | Designation |
|---|---|
| U.S. | Approved MIL-PRF-23699G Grade STD Approved SAE AS5780B Grade SPC |
| British | Approved DEF STAN 91-101 Grade OX-27 |
| French | Equivalent DCSEA 299/A |
| Russian | — |
| NATO Code | O-156 |
| Joint Service Designation | OX-27 |
| Pratt & Whitney | Approved 521C Type II |
| General Electric | Approved D-50 TF 1 |
| Allison | Approved EMS-53 (Obsolete) |
Common Qualified Products
| Product | Primary Military Specification | SAE / AS Specification | Notes |
|---|---|---|---|
| AeroShell 750 | MIL-PRF-6081 Grade 1010 (formerly MIL-L-6081) | None commonly associated | Ashless-dispersant piston engine oil for aviation piston engines. |
| AeroShell Ascender | MIL-PRF-23699 HTS | SAE AS5780 HPC | Fourth-generation 5 cSt turbine oil. NATO O-154 / OX-27. |
| AeroShell 500 | MIL-PRF-23699 STD | SAE AS5780 SPC | Standard 5 cSt turbine oil. |
| AeroShell 555 | DOD-L-85734A and MIL-PRF-23699 C/I | SAE AS5780 C/I | Helicopter transmission and high-load turbine oil. |
| AeroShell 560 | MIL-PRF-23699 HTS | SAE AS5780 HPC | High thermal stability turbine oil. |
| AeroShell 3 | Not a MIL spec product; British DEF STAN 91-99 | None | 3 cSt mineral turbine oil for older turbojets and APUs. |
| AeroShell 308 | MIL-PRF-5606 (formerly MIL-H-5606) | None (hydraulic fluid) | Mineral hydraulic fluid. NATO H-515. |
| AeroShell 390 | DEF STAN 91-94 (British) | None commonly used | 3 cSt synthetic turbine oil for older Rolls-Royce and Turbomeca engines. |
Properties — MIL-PRF-23699G Grade STD / SAE AS5780B Grade SPC
| Property | Specification | Typical |
|---|---|---|
| Oil type | Synthetic ester | Synthetic ester |
| Kinematic viscosity mm²/s — @ 100 °C | 4.90 to 5.40 | 5.17 |
| Kinematic viscosity mm²/s — @ 40 °C | 23.0 min | 25.26 |
| Kinematic viscosity mm²/s — @ −40 °C | 13000 max | 8996 |
| Flashpoint — Cleveland Open Cup (°C) | 246 min | 256 |
| Pourpoint (°C) | −54 max | <−54 |
| Total acidity (mgKOH/g) | 1 max | 0.11 |
| Evaporation loss — 6.5 hrs @ 204 °C (%m) | 10.0 max | 3.6 |
| Foaming | Must pass | Passes |
| Swelling of standard synthetic rubber SAE-AMS 3217/4, 72 hrs @ 204 °C (swell %) | 5 to 25 | Within limits (15%) |
| Elastomer compatibility — % weight change after 24/120 hrs: Fluorocarbon @ 200 °C | 10/15 max. | Within limits |
| Elastomer compatibility — LCS Fluorocarbon @ 200 °C | 10/20 max. | Within limits |
| Elastomer compatibility — Nitrile @ 130 °C | Report | Within limits |
| Elastomer compatibility — Silicone @ 175 °C | Report | Within limits |
| Elastomer compatibility — Perfluoroelastomer @ 200 °C | N/A | — |
| Thermal stability/corrosivity 96 hrs @ 274 °C — metal weight change (mg/cm) | 4 max | 0.5 |
| Thermal stability/corrosivity — viscosity change (%) | 5 max | 2.69 |
| Thermal stability/corrosivity — total acid number change (mgKOH/g) | 6 max | 2.03 |
| Corrosion & oxidation stability — 72 hrs @ 175 °C | Must pass | Passes |
| Corrosion & oxidation stability — 72 hrs @ 204 °C | Must pass | Passes |
| Corrosion & oxidation stability — 72 hrs @ 218 °C | Must pass | Passes |
| HLPS dynamic coking @ 375 °C, 20 hrs — deposit (mg) | Report | 1.34 average |
| Ryder gear test, relative rating (%) — Hercolube A | 102 | 117 |
| Bearing Test Rig Type 1 ½, 100 hrs — overall deposit demerit rating | 80.0 max | 51 |
| Bearing Test Rig — viscosity change @ 40 °C (%) | −5 to +30 | 18.25 |
| Bearing Test Rig — total acid number change (mgKOH/g) | 2 max | 0.63 |
| Bearing Test Rig — filter deposits (g) | 3 max | 0.70 |
| Sonic shear stability — viscosity change @ 40 °C (%) | 4 max | 0.19 |
| Trace metal content | Must pass | Passes |
| Sediment (mg/l) | 10 max | 0.77 |
| Ash (mg/l) | 1 max | 0.4 |
Equipment Manufacturer Approvals
AeroShell Turbine Oil 500 is approved for use in all models of the following engines:
| Manufacturer | Approved Engines / Models |
|---|---|
| Honeywell | TPE 331, GTCP 30, 36, 85, 331, 660 and 700 series APUs. ALF 502, LF507, LTS101, LTP101, T53, T55, AL5512, RE100, TCSP700, RE200 |
| Allison (Rolls-Royce) | 250 Series, 501, D13, T56, GMA 2100, GMA 3007 |
| BMW-Rolls-Royce | BR710, BR715 |
| Engine Alliance | GP7200 |
| Eurojet | EJ200 |
| GE | CF6, CT58, CF700, CJ610, CJ805, CF34, CT7, CT64 |
| Hamilton Sundstrand | APS 500, 100, 2000, 3000 |
| IAE | — |
| Motorlet | M601D, E and Z |
| Pratt & Whitney | JT3, JT4, JT8, JT9, JT12, PW4000, PW6000 |
| Pratt & Whitney Canada | JT15, PT6A, PT6T, ST6, PW100, PW200, PW300, PW500 |
| Rolls-Royce | RB211, -524, -535, Tay, Gnome, Spey, RB183, Adour, M45H, Viper (Series MK 301, 521, 522, 526, 535, 540, 601, 623 and 632) |
| Turbomeca | Adour, Ardiden, Arriel, Arrius, Arrius 1D, AST 600, Astazou XVI, Larzac, Makila, MTR390, RTM322, TM333, 526, 535, 540, 601, 623 and 632. Approved with restrictions*: Artouste, AST 950, Astazou, Turmo, Bastan |
MIL-PRF-23699 Property Calculators
Explore the full set of MIL-PRF-23699 property calculators on KasperCalc: