Im not sure if that would work or not. From what i remember sugars are fast energy, you get a sugar boost when you eat them but you burn it fast where as carbs take a long time to digest so give off energy over a longer length of time. Maybe give him some pasta and add a little sugar or honey to his water? Ive never sent a dog on a plane and have never heard about feeding honey in advance for anything. Hope you have a good flight :)