JPMorgan analyst C. Stephen Tusa says that at face value, he would view an acquisition of Rockwell Collins (COL) as a "mixed event" for United Technologies (UTX). Benefits include a solid strategic rationale that plays into the broader aerospace sector narrative and some earnings accretion, Tusa tells investors in a research note after Bloomberg reported Friday that United Technologies is mulling the deal. However, the potential size of the acquisitions dilutes the positives somewhat and makes achieving targeted returns a challenge, Tusa contends. He adds that a stock issuance may be required for United Technologies. The analyst has a Neutral rating on the shares.