Which ETFs effectively track these sectors?

There are ETFs that effectively track the sectors that complement the aerospace industry. Here are some examples:

1. **Industrial Equipment and Machinery**: The Industrial Select Sector SPDR Fund (XLI) provides exposure to companies involved in industrial equipment and machinery manufacturing.
2. **Information Technology**: The Select Sector SPDR Technology ETF (XLK) tracks the technology sector, which includes companies involved in software, semiconductors, and hardware.
3. **Materials Science and Engineering**: The Materials Select Sector SPDR Fund (XLB) tracks the materials sector, which includes companies involved in the manufacture of metals, chemicals, and other materials.
4. **Avionics and Electronics**: The Vanguard Information Technology ETF (VGT) provides exposure to companies involved in avionics and electronics, including those that manufacture aircraft and spacecraft electronics.

These ETFs offer investors the opportunity to gain exposure to the sectors that support the aerospace industry, allowing them to diversify their portfolios and potentially benefit from the growth of these complementary sectors.