•Combustion characteristics of limonene, Jet A-1, and blends are investigated.•Tested in a swirl stabilized combustor at different swirl air temperatures.•Maximum OH* and CH* intensities are observed near the dump plane of the combustor.•The flame temperature profile is in accordance with the loading % of limonene.•CO and NOx emissions decrease with an increase in the % of limonene in the blends. Biofuels are low carbon fuels and have emerged as an important source of energy for reducing pollutant emissions and greenhouse gas emissions in the aviation industry. In the present work, the spray combustion characteristics of limonene, Jet A-1, and limonene/Jet A-1 blends (10%, 30%, and 50% volumetric loading of limonene) have been experimentally investigated in a laboratory-scale swirl-stabilized combustor. To examine the effect of heated swirling air on the combustion of limonene, Jet A-1, and Jet A-1/limonene blends, the experiment has been conducted on non-preheat and two preheat conditions (swirling air temperature of 373 K and 473 K). Limonene is considered an emerging fuel alternative owing to its high calorific value and comparable physical properties with Jet A-1. The spray flame length of limonene is approximately 20% shorter than the flame of Jet A-1, while compared to the non-preheated case the flame length is reduced in preheat case (approximately 15% reduction in 373 K case and 25% reduction at 473 K). Compared to pure Jet A-1, the flames of limonene and limonene/Jet A-1 blends have given good results in terms of pollutant emissions and temperature profiles when limonene is added to Jet A-1. 50% limonene-loaded blends show a drop of 15% CO and neat limonene show a 35 % CO reduction. Additionally, 10%, 30%, and 50% limonene blends have shown better combustion characteristics compared to neat Jet A-1.