Not at all. There are several altitude reading devices that would give you an idea of what your aircraft looks like at 400 feet. For safeties sake I would suggest that if you know or suspect you will be flying above 400 ft AGL only do so with a spotter. I never fly my sailplanes without a spotter but I know it is at 400 ft plus when it comes off the hi-start. All my powered planes I keep within the pattern of the field.

Frank