# How do I calculate the impact of the winds aloft in this test question?

I was flying through this section in the ASA test prep book, I thought I had mastered this E6B. But this has me stumped:

I can’t do the math to figure out how many knots I’ve traveled. But in the answer it has me plotting a course of 280 (100 + 180) from the departure point. I cannot figure out for the life of me where they got this course.

I see that the winds are from 100 in the winds aloft, but I can’t imagine how I get a 100+180 course from that. I feel like I’ve missed some major concept.

• If the wind is coming from 100 degrees, which direction will the plane be blown? – StephenS Nov 22 '20 at 20:42
• Ok, that helps. 280 is opposite 100. Got it. But isn’t it still making a lot of assumptions like no wind correction and such? – rbsc Nov 22 '20 at 20:51
• I'm not sure I understand the question. You didn't mention which heading or course the question asks you to fly from the airport. E.g. heading 100 would take you directly into the wind; 280 would take you directly away from it etc. Or are you just asking about the effect of the winds only, and not what they mean for the final track of the aircraft? If you could quote the entire question I think it would be a lot clearer. – Pondlife Nov 23 '20 at 17:02
• @Pondlife That had me baffled too until I saw this is for the LSL (Light Sport-Lighter Than Air) test. – StephenS Nov 24 '20 at 1:49
• I didn't notice LSL, but with airspeed matching wind I was just starting to question whether this was for a balloon! @rbsc, did you realize this?! – Michael Hall Nov 24 '20 at 2:36