The graph I have (not monitored) shows OGE at 5000 ft and 23 C as okay at 1320 lb, so in theory you're fine. In practice, unless you have some very high terrain (obviously not in FLA) you'll be moving either backwards or forwards and almost certainly descending, so pointless exercise in an R22. Different with rad-alt etc.
Regarding the loss of a/s, that is a very common fault with inexperienced night flyers. During the day you rely on so many subconscious cues to adjust attitude that when you lose them at night or IMC, pitch control can become erratic. Having a small (or none?) ADI, poorly lit won't help at all either. Adding 5 degrees nose up over the normal approach attitude, at night with no horizon,is very difficult to spot unless you are monitoring closely. The rapid washing off of IAS is dramatic though. Try it in daytime from 40 kts, and see how long it takes to get to 0 kts. Then leave the power and watch the rate of descent build up. It's dramatic, and at night and low level it can be a killer. (BTW, don't get yourself into vortex ring recovering from the experiment!).
Flying onshore the effects can be ameliorated often with suburban lighting, roads etc. In remote areas or offshore it can be very easy to fall for it. Night deck landings in total blackness can end in a premature stop several hundred yards short, as the inexperienced pilot pays too much attention to the target and not enough to what's happening to the a/c.
With a/c that involve large attitude changes during the decelerative phase eg S76, you can be fooled by the apparent movement of the target down the windscreen, giving a false impression of overshooting or 'going high'. Obviously this can lead to problems, and the physiological cues can be very powerful, to the extent of disbelieving the instruments.
A particular problem you'll have in the R22 is its lack of cyclic trim, so you are reliant on a pitch attitude being maintained by your hand, rather than the stick being held in a trimmed position. This is where the importance of a good cyclic hand position can manifest itself.
The other phenomenom you may experience is the reverse ie you don't slow down soon enough and go sailing past the target. With no texture cues to gauge your groundspeed, a point source target can seem to remain distant with now change in aspect, until the last moment. Attempting to salvage the approach can then lead to the earlier problem, particularly if you lose sight of the target due to violent flaring.
As someone says above, treat night flying as semi IF, look out when you really have to, look in when you really have to and try to hone your other senses such as hearing. You can normally hear speed loss of that extent, similarly you can hear Nr decay or rise if you are mishandling the collective through overcontrolling. Remember that the a/c does not know it is night, so will require the same approach profiles etc. Don't drag it in slowly in the HV curve.
If in doubt, go round and try again.
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Another day in paradise
[This message has been edited by 212man (edited 03 January 2001).]
[This message has been edited by 212man (edited 04 January 2001).]