You're talking about spelling? That is basically irrelevant. Instead, you should look at the phonemes. In English we have words like "hospital" with H pronounced and others like "herb" (in American English) with the H not pronounced. Silent letters have no effect on the acoustics, obviously.
So if you have a French word with silent H, then it would have no sound. If it has an /h/ phoneme, it would probably sound similar to English (if [h] is an accurate description).
You might find this is a phonological pattern-- between vowels you get an H for example. I'm not sure about French.
In short, spelling and pronunciation do not (necessarily) have anything to do with each other: the phonetic form for "right" will be essentially identical to "write".