Hi mablehome,
May 5th is the national holiday in Japan.
We also have holidays on Apr.29, May 4th and May 6th.
There will be a big civil festival at Hirosima from may 3 to 5, so I think it will be difficult
to find a hotel in a nice price(4,500-9,000 yen/night) around Hiroshima...
When you cannnot find out the room , please check at around Kure-city or Tokuyama-city.
It will take about 1-1.5 Hrs from Iwakuni by train.
Please see this URL for the airshow;
http://www.friendship-day.net/" onclick="window.open(this.href);return false;
There will be no other airshows in Japan from May 1st to 6th.
FAQ for the JSDF airshow (which is held on Sunday):
The visiter a/cs usually come on Friday morning.
The B.I. usually have their rehearsal flt. on Saturday morning.
The visiter a/cs usually leave the base on Sunday afternoon, about 1400-1600pm.
There will be no flt. or quite less flt. on Monday.