Boeing vs. Rocket Lab: Which Aerospace Stock Is a Better Buy in 2026?

Rocket Lab is presented as the preferred aerospace investment, with FY2025 revenue up 38% to $601.8 million, backlog above $2 billion, and a conservative 0.1x debt-to-equity ratio. However, it remains unprofitable, posting a $198.2 million net loss and negative free cash flow of $321.8 million while trading at a steep 47.8x sales multiple. Boeing returned to FY2025 profitability with $89.5 billion of revenue and $2.2 billion of net income, but its roughly 10.0x debt-to-equity ratio, $1.9 billion negative free cash flow, production constraints, and defense-program charges leave its turnaround incomplete.

Analysis

The relevant distinction is not legacy aerospace versus space growth; it is balance-sheet optionality versus execution-adjusted valuation. BA’s vertically integrated supply chain should improve unit economics only after inventory, supplier quality, and certification bottlenecks normalize, meaning the near-term benefit is more likely reduced disruption than a rapid margin inflection. Its equity remains highly sensitive to delivery cadence and free-cash-flow conversion: a modest shortfall in monthly deliveries can disproportionately delay deleveraging and keep the multiple capped despite improving reported earnings.

RKLB’s valuation leaves little room for development slippage. The stock is effectively underwriting successful Neutron commercialization, sustained government demand, and acquisition integration before the business produces self-funding cash flow; therefore, a launch or schedule milestone matters more than quarterly revenue beats. The proposed IRDM transaction, if independently confirmed, would shift RKLB toward recurring communications cash flow but also introduces financing, regulatory, and integration risk—investors should not capitalize projected synergies before deal terms, funding sources, and pro forma leverage are verified.

Contrarianly, BA may offer the better 6-18 month risk-adjusted setup if operational milestones continue to de-risk, because investor expectations remain anchored to prior failures while commercial aviation supply scarcity supports pricing and aftermarket demand. Conversely, RKLB’s bullish narrative is crowded and vulnerable to a 20-30% valuation reset on any Neutron schedule revision, even if its core Electron and space-systems franchises continue growing. The article contains internally inconsistent cash-flow characterization and unverified transaction claims; neither should be traded without primary filings and company disclosures.

Key Decisions for Investors

• Establish a 6-12 month long BA / short RKLB dollar-neutral pair only after verifying BA’s latest delivery-rate authorization and RKLB’s Neutron schedule and cash runway. Thesis: BA’s operational de-risking can drive multiple expansion while RKLB is priced for execution perfection; target 15-20% relative return, exit if BA free-cash-flow guidance deteriorates or Neutron remains on schedule with contracted demand accelerating.
• For directional BA exposure, scale in around quarterly delivery and free-cash-flow updates rather than headline-driven rallies. Use a stop/reassessment trigger on renewed FAA production restrictions, a material labor disruption, or another downward revision to annual delivery/free-cash-flow guidance; the key upside catalyst over 1-3 quarters is evidence that supplier integration reduces rework and working-capital drag.
• Avoid adding outright RKLB common at current narrative-driven valuation until primary-source confirmation of the IRDM transaction structure, expected dilution, and Neutron capex profile. If exposure is required, use a defined-risk 6-9 month call spread sized for a successful Neutron milestone rather than unhedged equity; a schedule slip or launch anomaly would invalidate the setup.
• Monitor IRDM as a transaction-arbitrage alert rather than a recommendation: compare its trading price with confirmed consideration once definitive terms are available. A wide spread after formal announcement may reflect regulatory or financing risk, not a low-risk merger-arb opportunity.