I see where the UAE Mars probe has successfully entered obit. It won't land but just circle the planet collecting data. The Chinese and American probes will both attempt to land a probe on the surface. A whole lot more difficult. The American lander is supposed to have a helicopter on board. If they can pull that off it will be amazing.
Particularly since the atmospheric density is only .6% of sea level earth. Howard can tell you what density altitude that corresponds to.
Brett
p.s. 112,000 feet. Highest altitude achieved by a manned helicopter = 41,000 feet - only recently have helicopters been able to reach the top of Mt. Everest, at 29000 feet.