NWA has DTW & MSP, UA has SFO & LAX, AS has PDX & SEA, while USakaHP has LAS & PHX: all are about an hour flying time apart.
For giggles only, I looked up their timetables for this coming Monday, June 5th. Interpret if you care...

Northwest from SkyTeam Timetable:
NW740 MSP 0600 DTW 0838 757 1h38m
NW742 MSP 0652 DTW 0932 757 1h40m
NW752 MSP 0850 DTW 1132 320 1h42m
NW748 MSP 0855 DTW 1137 320 1h42m
NW768 MSP 1004 DTW 1252 320 1h48m
NW1690 MSP 1006 DTW 1254 320 1h48m
NW750 MSP 1120 DTW 1401 757 1h41m
NW754 MSP 1311 DTW 1600 757 1h49m
NW1892 MSP 1315 DTW 1604 D9S 1h49m
NW762 MSP 1322 DTW 1611 320 1h49m
NW766 MSP 1415 DTW 1701 D9S 1h46m
NW756 MSP 1510 DTW 1757 753 1h47m
NW746 MSP 1658 DTW 1942 320 1h44m
NW758 MSP 1705 DTW 1949 320 1h44m
NW846 MSP 1854 DTW 2141 757 1h47m
NW764 MSP 2100 DTW 2333 757 1h33m
NW760 MSP 2210 DTW 0042 +1 319 1h32m
---
NW739 DTW 0700 MSP 0748 753 1h48m
NW763 DTW 0845 MSP 0940 319 1h55m
NW741 DTW 0915 MSP 1010 753 1h55m
NW1231 DTW 1005 MSP 1059 319 1h54m
NW753 DTW 1133 MSP 1225 D95 1h52m
NW747 DTW 1225 MSP 1315 320 1h50m
NW749 DTW 1336 MSP 1425 320 1h49m
NW185 DTW 1510 MSP 1602 757 1h52m
NW105 DTW 1515 MSP 1607 757 1h52m
NW757 DTW 1704 MSP 1758 757 1h54m
NW399 DTW 1855 MSP 1949 320 1h54m
NW1275 DTW 1909 MSP 2003 320 1h54m
NW759 DTW 2049 MSP 2131 319 1h42m
NW481 DTW 2222 MSP 2306 320 1h44m

United from EasySchedule Online:
Los Angeles, CA (LAX) to San Francisco, CA (SFO) - June 5, 2006
Depart Arrive Via Duration Flight numbers Aircraft
6:16am 7:30am 1h14m UA63 752
6:56am 8:10am 1h14m UA1154 735
7:55am 9:09am 1h14m UA885 752
9:30am 10:48am 1h18m UA1152 752
10:00am 11:18am 1h18m UA930 752
11:12am 12:26pm 1h14m UA889 752
12:07pm 1:21pm 1h14m UA857 733
1:28pm 2:42pm 1h14m UA844 752
2:15pm 3:30pm 1h15m UA926 733
3:25pm 4:40pm 1h15m UA1146 733
4:05pm 5:20pm 1h15m UA1162 752
5:20pm 6:35pm 1h15m UA1168 733
5:45pm 7:00pm 1h15m UA1170 752
6:15pm 7:30pm 1h15m UA1172 733
7:10pm 8:25pm 1h15m UA49 752
8:45pm 10:00pm 1h15m UA188 319
10:10pm 11:25pm 1h15m UA987 752

San Francisco, CA (SFO) to Los Angeles, CA (LAX) - June 5, 2006
Depart Arrive Via Duration Flight numbers Aircraft
6:00am 7:26am 1h26m UA162 752
7:00am 8:26am 1h26m UA1193 752
7:30am 8:56am 1h26m UA1153 752
8:24am 9:50am 1h26m UA1155 752
9:33am 11:01am 1h28m UA979 733
10:00am 11:28am 1h28m UA858 752
10:50am 12:18pm 1h28m UA1250 319
11:35am 1:03pm 1h28m UA886 319
12:09pm 1:37pm 1h28m UA1166 752
2:00pm 3:22pm 1h22m UA1163 733
3:33pm 4:55pm 1h22m UA1165 752
4:10pm 5:32pm 1h22m UA927 733
5:20pm 6:42pm 1h22m UA1196 733
6:20pm 7:42pm 1h22m UA1171 735
8:00pm 9:30pm 1h30m UA931 319
9:00pm 10:30pm 1h30m UA845 735
10:30pm 11:50pm 1h20m UA1179 752

Alaska Airlines from www.alaskaair.com
PDX 5:00.AM SEA 6:00.AM 2168QX
PDX 6:00.AM SEA 6:54.AM 2246QX
PDX 6:20.AM SEA 7:10.AM 2453QX
PDX 6:30.AM SEA 7:22.AM 2298QX
PDX 7:00.AM SEA 7:55.AM 2290QX
PDX 7:30.AM SEA 8:25.AM 2272QX
PDX 8:00.AM SEA 8:49.AM 2434QX
PDX 8:20.AM SEA 9:12.AM 2046QX
PDX 8:30.AM SEA 9:19.AM 2386QX
PDX 9:00.AM SEA 9:52.AM 2260QX
PDX 9:30.AM SEA 10:22.AM 2050QX
PDX 10:00.AM SEA 10:55.AM 2256QX
PDX 10:30.AM SEA 11:25.AM 2284QX
PDX 11:00.AM SEA 11:55.AM 2200QX
PDX 11:30.AM SEA 12:22.PM 2270QX
PDX 12:00.PM SEA 12:54.PM 2060QX
PDX 12:30.PM SEA 1:25.PM 2286QX
PDX 1:00.PM SEA 1:52.PM 2130QX
PDX 1:30.PM SEA 2:22.PM 2196QX
PDX 2:00.PM SEA 2:59.PM 2252QX
PDX 2:30.PM SEA 3:22.PM 2268QX
PDX 3:00.PM SEA 3:47.PM 2308QX
PDX 3:30.PM SEA 4:22.PM 2280QX
PDX 4:00.PM SEA 4:52.PM 2294QX
PDX 4:30.PM SEA 5:24.PM 2048QX
PDX 5:00.PM SEA 5:52.PM 2276QX
PDX 5:30.PM SEA 6:17.PM 2430QX
PDX 6:00.PM SEA 6:52.PM 2124QX
PDX 6:30.PM SEA 7:30.PM 2288QX
PDX 7:00.PM SEA 7:52.PM 2242QX

City Time City Time Flight
SEA 6:00.AM PDX 6:54.AM 2203QX
SEA 6:30.AM PDX 7:19.AM 2187QX
SEA 7:00.AM PDX 7:50.AM 2297QX
SEA 7:30.AM PDX 8:24.AM 2255QX
SEA 8:00.AM PDX 8:50.AM 2229QX
SEA 8:30.AM PDX 9:14.AM 2435QX
SEA 9:00.AM PDX 9:49.AM 2257QX
SEA 9:30.AM PDX 10:19.AM 2243QX
SEA 10:00.AM PDX 10:49.AM 2269QX
SEA 10:30.AM PDX 11:19.AM 2221QX
SEA 11:00.AM PDX 11:52.AM 2271QX
SEA 11:30.AM PDX 12:19.PM 2273QX
SEA 12:00.PM PDX 12:52.PM 2279QX
SEA 12:30.PM PDX 1:22.PM 2211QX
SEA 1:00.PM PDX 1:49.PM 2281QX
SEA 1:30.PM PDX 2:24.PM 2289QX
SEA 2:00.PM PDX 2:45.PM 2309QX
SEA 2:30.PM PDX 3:20.PM 2295QX
SEA 3:00.PM PDX 3:49.PM 2191QX
SEA 3:30.PM PDX 4:19.PM 2189QX
SEA 4:00.PM PDX 4:44.PM 2429QX
SEA 4:30.PM PDX 5:19.PM 2251QX
SEA 5:00.PM PDX 5:49.PM 2283QX
SEA 5:30.PM PDX 6:19.PM 2299QX
SEA 6:00.PM PDX 6:54.PM 2263QX
SEA 6:30.PM PDX 7:15.PM 2361QX
SEA 7:00.PM PDX 7:44.PM 2379QX
SEA 7:30.PM PDX 8:19.PM 2169QX
SEA 8:00.PM PDX 8:42.PM 2454QX
SEA 8:30.PM PDX 9:19.PM 2277QX

US/HP AWA.pdf
LAS-PHX
6:45a 7:53a HP534 320 Daily 0
6:45a 7:53a ✈ US8079 320 Daily 0
7:00a 8:04a HP3 320 Daily 0
7:00a 8:04a ✈ US8156 320 Daily 0
8:15a 9:22a HP679 733 6 0
8:15a 9:22a ✈ US8119 733 6 0
9:40a 10:54a HP262 319 Daily 0
9:40a 10:54a ✈ US8223 319 Daily 0
9:55a 11:08a HP5 757 Daily 0
Above Eff. JUN1
9:55a 11:08a ✈ US8157 757 Daily 0
Above Eff. JUN1
10:10a 11:20a HP204 733 Daily 0
10:10a 11:20a ✈ US8019 733 Daily 0
11:34a 12:45p HP836 733 Daily 0
11:34a 12:45p ✈ US8293 733 Daily 0
12:55p 2:08p HP62 319 Daily 0
12:55p 2:08p ✈ US8186 319 Daily 0
3:05p 4:13p HP736 319 Daily 0
3:05p 4:13p ✈ US8369 319 Daily 0
4:03p 5:25p HP9 320 Daily 0
4:03p 5:25p ✈ US8000 320 Daily 0
5:20p 6:32p HP712 319 Daily 0
5:20p 6:32p ✈ US8273 319 Daily 0
7:10p 8:19p HP715 733 Daily 0
7:10p 8:19p ✈ US8515 733 Daily 0
8:50p 9:59p HP876 733 123 0
8:50p 9:59p ✈ US8456 733 123 0
9:35p 10:44p HP709 320 Daily 0
9:35p 10:44p ✈ US8524 320 Daily 0
10:57p 0:12a+1 HP136 319 Daily 0
10:57p 0:12a+1✈ US8259 319 Daily 0
11:59p 1:14a+1 HP99 319 Daily 0
11:59p 1:14a+1✈ US8360 319 Daily 0
PHX-LAS
6:00a 7:06a ❖ US5374 CR9 234 0
6:00a 7:06a ❖ HP6600 CR9 234 0
7:20a 8:29a HP720 757 Daily 0
7:20a 8:29a ✈ US8275 757 Daily 0
9:00a 10:21a HP894 319 Daily 0
9:00a 10:21a ✈ US8303 319 Daily 0
10:08a 11:18a HP461 320 Daily 0
10:08a 11:18a ✈ US8332 320 Daily 0
1:35p 2:39p HP64 320 Daily 0
1:35p 2:39p ✈ US8174 320 Daily 0
2:00p 3:02p HP485 733 6 0
2:00p 3:02p ✈ US8422 733 6 0
3:10p 4:18p HP710 319 Daily 0
3:10p 4:18p ✈ US8271 319 Daily 0
4:18p 5:22p HP694 320 Daily 0
4:18p 5:22p ✈ US8267 320 Daily 0
5:25p 6:27p HP719 733 Daily 0
5:25p 6:27p ✈ US8517 733 Daily 0
6:24p 7:33p HP798 319 Daily 0
6:24p 7:33p ✈ US8065 319 Daily 0
7:35p 8:45p HP463 320 Daily 0
7:35p 8:45p ✈ US8155 320 Daily 0
8:56p 9:58p HP690 320 Daily 0
8:56p 9:58p ✈ US8437 320 Daily 0
9:52p 11:05p HP423 733 Daily 0
9:52p 11:05p ✈ US8320 733 Daily 0