A new and distinct cultivar of Vanda plant named ‘SPCDW1521’ which is characterized by long, dark green foliage and large flowers which are loosely held on a tall inflorescence, violet sepals and petals with prominent dark violet reticulate venation, sepals and petals which are slightly spiraled in a propeller-like fashion, a very dark violet labellum, and the stability of these characteristics from generation to generation.
