These planes can tow trailers just like a truck. It could be the future of shipping

Summary

1. Additional fuel used during take-off, but then the glider would surf ‘on the wake of the air’.
2. Redundant planes could be used as gliders.
3. US military used gliders in World War II to deliver soldiers and supplies.

References

• Media Check: Fast Company - Media Bias Fact Check (HIGH CREDIBILITY) 
• Collections | The Runway (airforce.gov.au)
• RAAF RUNWAY: RATIONALE, GUIDELINES, LEARNING OUTCOMES, ETC.