The technology, introduced with the iPhone 6S, measures the pressure of a touch, performing different actions based on its depth. Apps can "peek" or "pop," showing a small amount of information before opening.
3D Touch builds on from Force Touch, which debuted in the Apple Watch and new 12-inch MacBook earlier in 2015.
The iPad Air, mini, and Pro do not currently have 3D Touch - and the report alleges that Apple is having trouble scaling the technology to accommodate the larger displays.
The 12.9-inch iPad Pro (which launched in November 2015) does not have 3D Touch, despite being launched after the iPhone 6S.
AppleInsider claims Apple is working on a new version of 3D Touch that is compatible with the larger display, but it is unclear if it will be ready for the launch of the iPad Air 3.
KGI Securities analyst Ming-Chi Kuo published a report yesterday claiming that the iPad Air 3 would ship in March 2016 without 3D Touch based on supply chain issues.