5G is the enabling technology for a new generation of smart phones and IoT connected devices, promising low latency, high-bandwidth communications. The commercial potential for the technology is massive, and as it rolls out in the US, an unexpected consequence of 5G has emerged: interference with aircraft radar altimeters. Radar altimeters are safety critical, basic flight instruments for commercial airliners, and the use reflected beams of radiofrequency radiation there similar to the signals emitted by wireless service providers. 5G towers operating the vicinity of airports could jam radar altimeters signals during final approach to a runway, which in low visibility conditions could be safety critical. The FAA is scrambling to certify which radar altimeter models and aircraft are safe for use in 5G environments, but not all airplanes have yet been approved, and regional jets are still under study.Small modular reactors represent the new wave of nuclear fission technology which promises to deliver clean, carbon free power at low cost. Compared to traditional light and heavy water reactor designs, SMRs are designed to operate without large containment structures or the complex and layered safety systems necessary for traditional reactors. Hyundai Engineering has taken a $30 million equity stake in Seattle-based Ultra Safe Nuclear Corporation, were building a test reactor to demonstrate the company’s novel single pass uranium fuel cycle. Using encapsulated TRISO fuel, the design will deliver 5 MW-e in HR transportable form factor that can be deployed almost anywhere. The reactors pre-fuels at the factory and is simply replaced after 20 years of operation. The high-temperature gas cooled design requires minimal human monitoring and shows interesting possibilities for process and space heating applications as well as thermal power generation. The test unit is scheduled to go online in 2026 at Chalk River in Ontario, Canada.Access all episodes of This Week in Engineering on engineering.com TV along with all of our other series.