To convert Delta's speed from miles per hour to kilometers per hour, we can use the conversion factor that 1 kilometer is approximately equal to 0.62 miles.
First, we can find out how many miles are in one kilometer:
\[ 1 \text{ kilometer} = 0.62 \text{ miles} \]
Now, we can find out how many kilometers are in one mile by taking the reciprocal:
\[ 1 \text{ mile} \approx \frac{1}{0.62} \text{ kilometers} \approx 1.613 \text{ kilometers} \]
Next, we can convert 17 miles per hour to kilometers per hour by multiplying by the conversion factor:
\[ 17 \text{ miles per hour} \times 1.613 \text{ kilometers per mile} \approx 27.4 \text{ kilometers per hour} \]
So, Delta's speed in kilometers per hour is approximately 27.4 kilometers per hour when rounded to the nearest tenth.
Thus, the answer is:
27.4