htaccess redirect to index.html not to / ?

Hi,
I don't want visitors to land on domain.tld but on www.domain.tld/index.html
In the moment I use this .htaccess:

RewriteEngine on
RewriteBase /
RewriteCond %{HTTP_HOST} ^[^.]*\.[^.]*$
RewriteRule ^ http://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L]

Can anybody tell me how to modify the htaccess so that a visitor automatically gets to .../index.html and not to / ?
Each time I try my luck, I crash the server