Indololwane engu-90 degree iwuhlobo lwendololwane ene-engeli engu-90 degrees, esetshenziswa kakhulu ukushintsha indlela yokugeleza kwepayipi. Ngokuvamile isetshenziswa ezinhlelweni zamapayipi lapho kudingeka khona ama-engeli agobile aqinile, njengalapho ezinye izinto zamapayipi zidinga ukuxhunywa ngaphambi noma ngemva kokugoba.