PPG P/S 890 AMS-S-8802 Type 2 Class B-2 Fuel Tank Sealant – Pint Kit Extended Working Life

PPG P/S 890 is a premium two-component polysulfide fuel tank sealant meeting AMS-S-8802 Type 2 Class B-2 specification. The Class B-2 designation indicates a longer working life (pot life after mixing) compared to Class B or B-1/2 products, making P/S 890 the preferred choice for large, complex fuel tank sealing operations where more time is needed to apply sealant to multiple joints before the mixed material begins to gel.

The extended Class B-2 working life allows technicians to mix a larger quantity of sealant and work through multiple joints or large-area applications without the time pressure associated with shorter working life grades. This reduces the number of mix cycles required during a maintenance event, minimizing material waste from partially-used batches that exceed their working life before the sealant can be applied.

P/S 890 provides the same outstanding fuel resistance, adhesion, and flexibility as other AMS-S-8802 Type 2 polysulfide sealants in the PPG range, with full resistance to aviation fuel immersion, excellent adhesion on aluminum and steel fuel tank structures, and the long-term elastomeric flexibility required for seal integrity over thousands of flight cycles.

Technical Information

PPG P/S 890 achieves its Class B-2 extended working life through a modified accelerator system that slows the polysulfide crosslinking reaction rate compared to Class B or B-1/2 formulations, providing approximately twice the application time before the sealant begins to gel. Despite the slower initial cure rate, the fully cured P/S 890 achieves the same final mechanical properties and chemical resistance as faster-curing grades, meeting all AMS-S-8802 Type 2 specification requirements at the specified cure completion time.

For temperature-sensitive applications, extended working life sealants like Class B-2 provide additional benefit at elevated ambient temperatures where cure rate is accelerated compared to standard conditions. In hot climate facilities or summer maintenance conditions where standard working life sealants may gel prematurely, P/S 890 Class B-2 provides the additional working time margin needed to complete complex sealant applications before the material becomes unworkable.

Like all PPG polysulfide fuel tank sealants, P/S 890 must be mixed in the exact ratio specified in the PPG technical data sheet. Ratio deviation can result in under-cured or incorrectly cured sealant with reduced fuel resistance and mechanical properties that may not meet AMS-S-8802 specification requirements. The pint kit format provides pre-measured components to ensure correct ratio when the full kit is mixed as a single batch.

Why Choose PPG P/S 890 Class B-2?

• ✅ AMS-S-8802 Type 2 Class B-2 — Extended working life fuel tank sealant
• ✅ Longer Application Time — Ideal for large, complex sealing operations
• ✅ Reduces Material Waste — Fewer mix cycles, less expired sealant
• ✅ Hot Weather Advantage — More working time buffer at elevated temperatures
• ✅ Full Fuel Resistance — Jet A, Jet A-1, JP-4, JP-8 immersion rated

Applications and Compatible Aircraft

PPG P/S 890 Class B-2 is used for large aircraft fuel tank sealing operations, multi-joint maintenance events, and hot-weather sealing applications on commercial, business, and military aircraft where AMS-S-8802 Type 2 extended working life polysulfide fuel tank sealant is required.

Frequently Asked Questions

Q: What is the difference between Class B-1/2 and Class B-2 fuel tank sealant?
A: Class B-2 has a longer working life (pot life after mixing) than Class B-1/2, providing more application time before the sealant begins to gel. Class B-2 is preferred for large, complex sealing jobs where more time is needed to apply sealant to multiple joints from a single mixed batch.

Q: Is PPG P/S 890 approved for Boeing and Airbus aircraft?
A: P/S 890 is qualified to AMS-S-8802 Type 2 specification and is approved by major commercial and military OEMs. Verify the specific approval for your aircraft type in the applicable AMM or PPG approval documentation.

Q: What is the MPN for PPG P/S 890 Class B-2 Pint?
A: MPN is 08B902AM012PT.

Q: Can P/S 890 be used for both faying surface and fillet sealing?
A: Yes. P/S 890 can be applied as a faying surface sealant (brush application between mating surfaces before assembly) and as a fillet sealant (extrusion gun or spatula application to form a fillet bead along joint edges) depending on the sealing application.

Q: How does temperature affect P/S 890 Class B-2 working life?
A: Like all polysulfide sealants, P/S 890 cure rate and working life are temperature-dependent. Higher temperatures accelerate cure and shorten working life, while lower temperatures slow cure and extend working life. Refer to the P/S 890 TDS for working life guidance at various application temperatures.