I am going to go fly my airplane for the first time in a few years tomorrow (with instructor). I purchased a new battery and charged it up about a month ago to tweak the throws, etc. I just checked the voltage and its borderline between charge and recharge on the volt meter. I do not have a cycler, can I just turn on the receiver and the transmitter and let them stay on for a few hours to drain the batteries down, then recharge overnight to ensure maximum charge?

Or should I just charge as is?

Just recharge overnight with the wall wart charger that came with your transmitter. Do not discharge them unless you can monitor the voltage and stop the discharge when they get to 1 volt per cell or so. Cycling serves no purpose unless you intend to check the capacity of your pack.

Note: I assume you have a NiCd or NiMH pack. If it is something else then ignore my advice.

What people have been noticing is new packs need to be cycled about 4 times before they will charge fully, this is both NIMH and NICD. Years ago I used to just turn on my plane and radio and operate them like I was flying until the plane control surfaces quit operating then I would charge the battery again. It seemed to work but I had no real way of telling? Didn't hurt anything. These days I cycle all my new packs several times to make sure they are up to peak power. Some wall warts take longer then just over night to charge a pack too, it isn't the charger as much as what is over night??

take a set of old christmas lights and cut off a string of 3 lights, plug that into the battery while you are watching tv or sitting on the compy. once you notice the lights dimming quickly unplug the lights and charge up the batt. you can doubble or tripple the lights on the battery to drain them faster.

My experience (yours may differ) is that the increase in capacity achieved by cycling a new pack is insignificant. I replaced NiCd packs on four planes this spring. I cycled each new pack several times using a C/10 charger before I put it in its plane. These were 700 mAh Sanyo AA cell packs. The change in capacity from first cycle to last was less than 30 mAh.
I did the same with some Duracell 2700 mAh NiMH loose cells that I use for my bicycle lights and also with some Eneloop 2000 mAh cells. Again, the capacity change was not worth worrying about, maybe 100 mAh.

I suspect the 'conditioning cycles' are more important if you are going to use a peak detect charger. Then conditioning the cells with several long C/10 charges may be important. But the OP is presumably using a C/10 wall wart.

The only danger with discharging into a load is the possibility of driving the weakest cell into reverse charge. That is said to be damaging to the cell. This is the reason to stop the discharge at 1V per cell, i.e. 4.0 V for a 4-cell pack.

Anyway, I don't think the OP will be able to discharge into a load through his charge jack unless the diode has been shorted. There are lots of old posts on this, search on "transmitter diode".