Fig. 1.
![Changes in the power [hp] of aircraft engines in the period 1903–1918 [7, 12, 15, 26, 29,30,31, 33,34,35,36,37,38,39,40,41,42].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_001.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=6c5e79c54526c092e24e0bc089f5c8f5752d4324f5187c8be4ea745bd15aa4af&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 2.
![Changes in the ratio of aircraft engines’ power to their weight [hp/kg] in the period 1903–1918 [7, 12, 15, 26, 29,30,31, 33,34,35,36,37,38,39,40,41,42].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_002.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=ac4ec2b7528fd30662a330de1b68ab07d733d78bb40ccebd0d84f407801bea4a&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 3.
![Changes in the ratio of aircraft engines’ power to their displacement volume [hp/dm3] in the period 1903–1918 [7, 12, 15, 26, 29,30,31, 33,34,35,36,37,38,39,40,41,42].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_003.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=27c30aa57538cc6e4446b3570e438a8149abb05f7e28aab4b5b5e9fa9ae6d1e3&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 4.
![Changes in maximum revolutions per minute of the crankshaft [rpm] of aircraft engines in the period 1903–1918 [7, 12, 15, 26, 29,30,31, 33,34,35,36,37,38,39,40,41,42].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_004.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=57f75da785086a1db7d3d5b7fe468f03b54d0830a3287ce951bc0b8dfb9094ba&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 5.
![Changes in power [hp] of radial and inline engines in the period 1903–1918 [7, 12, 15, 26, 29,30,31, 33,34,35,36,37,38,39,40,41,42].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_005.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=0ba6c15c410452babb55b0383708baf69d66579e9283919b21c74e005e2d0c0e&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 6.
![Changes in the ratio of radial and inline engines to their displacement volume [hp/dm3] in the period 1903–1918 [7, 12, 15, 26, 29,30,31, 33,34,35,36,37,38,39,40,41,42].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_006.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=25d40414e89f7967caf3cd7c274cc15bc7793246c28a55c146eeefc4f827bcd8&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 7.
![Changes in the ratio of radial and inline engines’ power to their weight [hp/kg] in the period 1903–1918 [7, 12, 15, 26, 29,30,31, 33,34,35,36,37,38,39,40,41,42].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_007.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=c1c3f7b11c99c2d6091a4ceac12b65e366dd0e544d2fdb81876c3f3e522de311&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 8.
![Changes in power [hp] of aircraft engines in the period 1918–1939 [1,2,3,4, 10– 13,14,15,16,17, 27,28,29,30,31, 49, 51, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_008.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=f5e57cfbda3ce9a19807a273987af166c2514ab833386b22f55abf00ea44b825&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 9.
![Changes in the ratio of aircraft engines’ power to their weight [hp/kg] in the period 1918–1939 [1,2,3,4, 10, 13,14,15,16,17, 27,28,29,30,31, 49, 51, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_009.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=b83f03564914f5920c7d6d042c0c680ec5217a3009fc8e87200b830d3e9c1a28&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 10.
![Changes in the ratio of aircraft engines’ power to their displacement volume [hp/dm3] in the period 1918–1939 [1,2,3,4, 10, 13,14,15,16,17, 27,28,29,30,31, 49, 51, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_010.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=b19882e56a4d8e2fde3adfe50be4ee036871642f7669602bf2ae669d2146f418&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 11.
![Changes in maximum revolutions per minute of the crankshaft [rpm] of aircraft engines in the period 1918–1939 [1,2,3,4, 10, 13,14,15,16,17, 27,28,29,30,31, 49, 51, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_011.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=97a62aa1068132114b14e4188deccbec1ce79877271e9a2068ec05c8d1b23b6d&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 12.
![Changes in power [hp] of radial and inline engines in the period 1918–1939 [1,2,3,4, 10, 13,14,15,16,17, 27,28,29,30,31, 49, 51, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_012.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=68d431e09b8abf430825cf0c46e21cc7449e3ab413d6ee6bd1f0afc3f4b1fc5c&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 13.
![Changes in the ratio of radial and inline engines’ power to their weight [hp/kg] in the period 1918–1939 [1,2,3,4, 10, 13,14,15,16,17, 27,28,29,30,31, 49, 51, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_013.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=9b28fd5b98eccd98e57c24f94d9c61f0419583b0c2a209f842ebe820485072c9&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 14.
![Changes in the ratio of radial and inline engines to their displacement volume [hp/dm3] in the period 1918–1939 [1,2,3,4, 10, 13,14,15,16,17, 27,28,29,30,31, 49, 51, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_014.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=a9a24b160b6f555f4e24073773b42aedb57d3adb3f3fb9bdadc884355333f58d&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 15.
![Changes in maximum revolutions per minute of the crankshaft [rpm] of radial and inline engines in the period 1918–1939 [1,2,3,4, 10, 13,14,15,16,17, 27,28,29,30,31, 49, 51, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_015.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=d6a0cc61247bd61e0c70d948d4de1d9428df4daca7868b9c18b5f454a68b422b&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 16.
![Changes in power [hp] of aircraft engines in the period 1939–1945 [1,2,3,4,5, 14, 17, 21, 24, 28, 29, 45, 49,50,51,52, 58, 66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_016.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=e42b43c322382f959d8d76a2e7bc2de6f1ab0d897aa0b44422c85acafa8b5ecc&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 17.
![Changes in the ratio of aircraft engines’ power to their weight [hp/kg] in the period 1939–1945 [1,2,3,4,5, 14, 17, 21, 24, 28, 29, 45, 49,50,51,52, 58, 66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_017.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=93664812f398976b58f561c5d465378f43dc9199445107b66f5e58d1b63f49ef&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 18.
![Changes in the ratio of aircraft engines’ power to their displacement volume [hp/dm3] 1939–1945 [1,2,3,4,5, 14, 17, 21, 24, 28, 29, 45, 49,50,51,52, 58, 66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_018.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=13c352334efdb93692582daacb7959490773b96aefc1e1d67f17db6871020510&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 19.
![Changes in maximum revolutions per minute of the crankshaft [rpm] of aircraft engines in the period 1939–1945 [1,2,3,4,5, 14, 17, 21, 24, 28, 29, 45, 49,50,51,52, 58, 66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_019.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=3c86683b3597f2d23beec1123483411939b5fefab8b3a6da0a118d8c656a4698&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 20.
![Changes in power [hp] of radial and inline engines in the period 1939–1945 [1,2,3,4,5, 14, 17, 21, 24, 28, 29, 45, 49,50,51,52, 58, 66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_020.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=77d0afb73496984f66c00994045f34c52a89d4fe080fe7759b6a1ff81fc9c789&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 21.
![Changes in the ratio of radial and inline engines to their displacement volume [hp/dm3] in the period 1939–1945 [1,2,3,4,5, 14, 17, 21, 24, 28, 29, 45, 49,50,51,52, 58, 66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_021.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=0988402950668a0ecc1c5f132538f38f9b311f8af717e8012e8922546896c29c&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 22.
![Changes in the ratio of radial and inline engines’ power to their weight [hp/kg] in the period 1939–1945 [1,2,3,4,5, 14, 17, 21, 24, 28, 29, 45, 49,50,51,52, 58, 66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_022.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=96243f139936712caacc8816ed38053cec5ab8690964352daacbd315229ae60f&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 23.
![Changes in maximum revolutions per minute of the crankshaft [rpm] of radial and inline engines in the period 1939–1945 [1,2,3,4,5, 14, 17, 21, 24, 28, 29, 45, 49,50,51,52, 58, 66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_023.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=89716989046ae03055bfef2da215d37b78a6bbae8e0c0b576a4b1d1476459578&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 24.
![Changes in power [hp] of aircraft engines in the years 1903–1945 [1,2,3,4,5, 7, 10, 12,13,14,15,16,17, 21, 24, 26,27,28,29,30,31, 33,34,35,36,37,38,39,40,41,42, 45, 49,50,51,52, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_024.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=ce8b8d6d0fa784736888ca363ef4ed9d0a980a58fe7a96080d92d977b1eb3213&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 25.
![Changes in the ratio of aircraft engines’ power to their displacement volume [hp/dm3] in the years 1903–1945 [1,2,3,4,5, 7, 10, 12,13,14,15,16,17, 21, 24, 26,27,28,29,30,31, 33,34,35,36,37,38,39,40,41,42, 45, 49,50,51,52, 54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70, 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89].](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/67f6ed7c8d1bec042eaca24e/j_tar-2025-0001_fig_025.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKCS4CUOUS%2F20260213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20260213T225747Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECoaDGV1LWNlbnRyYWwtMSJHMEUCIQC%2BWmZpkl0pC4f2%2B06QQE1rq0x7MOLyyfIxynoJoxgqigIgNgxU5qWmGSH06LqL8awSMdi5SOmgzFoMAyjwNPY7eRcqxgUI8%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARACGgw5NjMxMzQyODk5NDAiDDh1m8x3PbdVBLK9aiqaBdffZHJ9R9g6WBeCN4%2BKts%2BILjy36U41raLk7he%2FBnD0uuNbbB2B%2Fb4XoCizCdGzyYyM8EgChI4Nl6MihnF1HS2ykY8OlS6%2BeSMT8635qr0zlNATemQZo3zWyrAN9jd4NiCAGlX78dz4Pjxry1aPE9vPUI0%2FeBGNcZYEZydIBKM1crreNYh5TM4%2Buqei%2Bn%2Fqog9bd3n1vuJlGin18W9wszc3q0tvD9dVofPyQTxMCS0Hr4hFH9DFtVuFi9nbWsIYQ6Tx%2FIgHLTjg8D%2B5637OzqrzeQPAmlzS%2BABue1YiarhQlZcfad676lKqyMHHBc2hgnzDhMN2GHdQOfN6w68PZN9xyMeFbmAj3i2Io4cwtri4tKIyvWQIAzghLentecKiGdkgOyandLUd%2F9OvH5CR4y%2FEbvGhnGcZ5%2BOMiYNfb6gMt5AbMwezka5I8vFPnFtW8Jo%2FmD51t%2BvYbdgyAfVuSR0MK3LoUXXZC1OKo8kn5rzYYWIe5nw%2FO9sl2u42HTmjCAEp37dscG5BX%2BmiNMGM2YVSW0xDVtuoqAVp3tON7K0PTA2UmNJQBDdkuiyVCLHV%2Fck0PcxMkRtA5d9Szai2eFiyyP1yiQHfVJ729McIVuipo%2Bm%2B1yJBbq3%2FpkiWdDtdJSiHb%2BCu%2BPKOPeZVVEOqXst9IwEUBvOciqnGLofksAkbJ1Ct%2FB0j1iC5xNCGcgrl5hli3SvAzTW8xCrWhWIvdjpT6JVRA%2BV5QFnaY6RwbFdDx2EpZYaEN1VURvF%2F%2F%2F7ycCjmbKBy7uUZBBmjy9Lkos7t%2F98QwhZNC9eM5nSMpfMHU8CbkmSz06xyiIdGNI1C9aFN6Vviwm9krwvhAmqp%2FQTC%2BlsSGLEoVOcnNVS6mScVlP3VSS8N79ZMcDD5x73MBjqxARqc29NE%2Bm0TlDmfahdi83aqUFOySUNGQmBS1BgxxdE33DiPJ5HjFhwnMDNZcL3WXBrN9YHKRLda2hxm6ur8svsoNZt5cwC1IG%2FqVUFdggfkKUQAz%2FdlDc9AiKzOHUZoWFy9SR7NA3tYtMXJa%2BYcD2C8Ntm4VYuYDQwRrztRfGzZ4tUZIyT8FcCs%2Bqyaqp3LkNf0eA3E9RD1padepVaorbaAYzM2bORGC1%2Bk3EG%2BQyMz8w%3D%3D&X-Amz-Signature=c5bef24047ae0f08c5d349021162aadb98c61a42a8e210297474a530ef73a24d&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Comparison of the Manly-Balzer and Wright Flyer I engines [1, 14, 16, 19–20]_
| Name | Manly-Balzer | Wright Flyer I |
|---|---|---|
| Power [hp] | 52 | 16 |
| Weight [kg] | 62 | 81.4 |
| Displacement [dm3] | 8.85 | 3.28 |
| Revolutions per minute [rpm] | 950 | 1025 |
| Power-to-weight ratio [hp/kg] | 0.839 | 0.197 |
| Power-to-displacement ratio [hp/dm3] | 5.876 | 4.878 |
| Weight of 1 dm3 of displacement [kg/dm3] | 7.006 | 24.817 |