Questions for your students:
What limits aircraft speed?
Why are commercial flights not supersonic?
How do we get to the next generation of aircraft?
In 2015 the Japanese Aerospace Exploration Association (JAXA) completed the first successful test of supersonic boom reduction due to geometric design. Sonic boom reduction is the crucial design point that has to be improved in order to allow hypersonic travel for commercial use. Since the Concorde from Air France crashed in 2000, supersonic travel became illegal worldwide over land. NASA, JAXA and a handful of private aerospace organizations are participating in research to reduce the effect of the sonic boom. The reduction of the sonic boom will allow for safe supersonic travel over the mainland and testing new geometries is key.
Many current supersonic and hypersonic vehicles are currently being made as unmanned and will be a stepping stone technology for weapons. However the Lockheed Martin SR-72 will be a stepping-stone to civilian travel. Lockheed will accomplish this by making the vehicle launch from the ground with a normal turbo engine getting the vehicle up to Mach 3. Once reaching an appropriate altitude the vehicle will transfer thrust to the scramjet getting the vehicle up to Mach 5+. Both engines will feed off the same inlet and have the same exhaust ports. This dual engine system is the key to not only get supersonic travel but also hypersonic travel for commercial travel.