I thought about sending this as a PM, but realized it will probably be of greater assistance to everyone if I go through it here.
First off, it's pretty good. You seem enthusiastic and show you really do love the sport. As a generic starting point, it's decent.
First things first, it's too long. You have some excessive stuff in here in which youre resume should be enough. Also, you should just include you're resume anyway. Most positions you will be applying to will give you the option to fill out an online application and either copy and paste a cover letter or upload a pdf or .doc. Always fill out every possible option and make sure to upload your resume and pdf as a 2 page pdf in which the text is selectable. This will give you're application/resume a lot more chances to be picked up by any searchers scanning resumes for key words by HR departments. It also gives you an opportunity to make you're cover letter and resume cohesive so that when printed, they match and are pleasing to the eye and more likely to be viewed as a whole.
Moving on... The questions, although good in theory, they just add length. You should start off with a power statement, not asking them the questions in which they clearly are looking for. A second option is to play to the company, but this would be company specific.
Your "professional" statement comes off as a bit arrogant. The sort of, while you only did this over 5 years, I did all this and still had a "professional" job in the ski industry. You could shorten the paragraph dramatically by saying something like while com pinging your Civil Engineering degree, your passion for skiing motivated you to maintain an amazing position with level 1 in which you... list the things you did.
You then have a strange transition. You did all this shit... then you built skis. Perhaps this would be a better time to correlate your degree with your passion. How through your degree, time in Alaska, and position with level 1, you wanted to apply your engineering skills to what your passion is. Thus begun your affair with ski making. You then state that you've switched from moment to only working with your own skis. You shouldn't mention the ski company you were on. Bad taste if you're applying for another company. Also, this again has a sense of arrogance where it should be passion. So perhaps something more on the lines of, "after my first run of 6 pairs, I realized there was no better way to progress, improve, and build upon my own skills than solely building, skiing, and filming my own skis. Since I have learned x,y, and z about building and feel that blah blah blah would do x, y, and z for your company.
If you change the tone through the letter to how skiing has influenced everything, you won't need the ski design engineer dream job paragraph. They will know that you are willing to put in every single effort needed to perform the job.. even if some days you do spend 40 hours at a desk (because that will likely happen on occasion).
Then you thank them for their time and say "I look forward to hearing from you" is spot on. It shows confidence and instantly puts the idea of contacting you into the reviewer's mind.
