Altima and Sol are very easy tracks to succeed in the A+ Challenge. All A+ challenges are easy when you become first place, in all honesty the biggest obstacle is just getting ahead of them because of their tendency to shove you around and launch missiles and such is so distracting. Altima and Sol offer an abundance of barrel roll opportunities to allow you to get ahead of everybody else. I have a few tips to help succeed in these events.

Altima

The first thing you should do before you cross the line is shift over to the far left. This will allow you to handle the corners at the beginning without much airbrake use. Make sure you just miss the far right bend and turn sharply right to enter the first skill cut. Here make sure you keep airbraking to a minimum, hitting the right wall is much better than hitting the left one. Experiment with different ships to see how much airbraking needs to be done to get through cleanly. After the barrel roll you should be in 5-7th place already. When you get to the Altima Drop pull the nose up to lift you onto the second level. reaching this means that you don't need to travel all the way down to the bottom of the chasm and back up again. You'll also have much less airtime which would prevent you from gaining too much air resistance from flying. This should put you in 1st-3rd place.

The final skillcut is much more easy to enter than the one near the start but more difficult to make it through cleanly. Firstly, it's a good idea to turn your craft to the left as you fly into it, just as if you are taking the original corner too late. The instant you enter the tunnel tap the right airbrake to get you through the corner. As soon as you see the light at the end of the tunnel sideshift onto the speedpad to exit.

Sol

Other than "Don't fall off"...
Take the left route at the tracksplit. Keep to the left and time your pitch downward so you can barrel roll as you hit the end of that part of the track before you fly down to the track again in which case you can barrel roll a second time before reaching it. If you have a turbo after you reach the second skillcut you can ignore it altogether and aim for the other side of this large corner past all the arrow signs, pull the nose up and barrel roll in mid air. You should land perfectly on the other side of the track. Otherwise take the skillcut. (Don't do this if you have pilot assist on, even "Normal" pilot assist, it will try to pull you back onto the track and will slow you down making you fall. Shouldn't really be using it in the first place though). The final skillcut is one of the most risky in the entire game. This is what would make this track ideal for the AG Systems Speed or FEISAR Speed as the airbrakes will try to pull you down so for heavier ships you'll need to be twitchy with them. Light ships however should handle this fairly easily.

I hope at least some of this was beneficial to someone. Took me a long time to put together.