Ionic emulate ios does not start the emulator

When I run the below commands, instead of starting the emulator and displaying the app I get NO feedback from the prompt:

SMV:firstIonicApp$ ionic platform add ios
Updated the hooks directory to have execute permissions
Platform ios already added.
SMV:firstIonicApp $ ionic build ios
SMV:firstIonicApp $ ionic emulate ios
SMV:firstIonicApp $

I am running node v4.1.0 along with the following installed globally:

├── bower@1.5.2
├── cordova@5.3.1
├── firebase-tools@1.2.0
├── flightplan@0.6.4
├── gulp@3.9.0
├── ionic@1.6.4
├── ios-sim@5.0.1
├── node-inspector@0.10.2
├── npm@2.14.1
└── pm2@0.14.3

My system information:

Cordova CLI: 5.3.1
Gulp version: CLI version 3.9.0
Gulp local:
Ionic Version: 1.1.0
Ionic CLI Version: 1.6.4
Ionic App Lib Version: 0.3.8
ios-deploy version: 1.7.0
ios-sim version: 5.0.1
OS: Mac OS X Yosemite
Node Version: v4.1.0
Xcode version: Xcode 7.0 Build version 7A220