Unless you know what you're doing, you could make it worse.

My thought would be to generate a text message to someone or maybe to 911 and someone else (for relay to 911) and maybe try flying the phone on a kite. Leave the cellphone antenna as is and just het the phone higher. Whenever it makes contact it should send the message. Much more reliable than a continuing conversation with a 911 operator who may not have a capability to read your position anyway.