| Aberdeen Regional (ABR) | Aberdeen | SD | Crystal to Aberdeen Regional |
| Antrim County (ACB) | Bellaire | MI | Crystal to Antrim County |
| Albert Lea Municipal (AEL) | Albert Lea | MN | Crystal to Albert Lea Municipal |
| Amery Municipal (AHH) | Amery | WI | Crystal to Amery Municipal |
| Atlantic Municipal (AIO) | Atlantic | IA | Crystal to Atlantic Municipal |
| Waterloo Regional (ALO) | Waterloo | IA | Crystal to Waterloo Regional |
| Ames Municipal (AMW) | Ames | IA | Crystal to Ames Municipal |
| Ainsworth Regional (ANW) | Ainsworth | NE | Crystal to Ainsworth Regional |
| Lakeland/Noble F. Lee Memorial Field (ARV) | Minocqua | WI | Crystal to Lakeland/Noble F. Lee Memorial Field |
| John F Kennedy Memorial (ASX) | Ashland | WI | Crystal to John F Kennedy Memorial |
| Ashley Municipal (ASY) | Ashley | ND | Crystal to Ashley Municipal |
| Appleton International (ATW) | Appleton | WI | Crystal to Appleton International |
| Watertown Regional (ATY) | Watertown | SD | Crystal to Watertown Regional |
| Austin Municipal (AUM) | Austin | MN | Crystal to Austin Municipal |
| Wausau Downtown (AUW) | Wausau | WI | Crystal to Wausau Downtown |
| Chicago/Aurora Municipal (AUZ) | Chicago | IL | Crystal to Chicago/Aurora Municipal |
| Algona Municipal (AXG) | Algona | IA | Crystal to Algona Municipal |
| Chandler Field (AXN) | Alexandria | MN | Crystal to Chandler Field |
| Benson Municipal (BBB) | Benson | MN | Crystal to Benson Municipal |
| Broken Bow Municipal/Keith Glaze Field (BBW) | Broken Bow | NE | Crystal to Broken Bow Municipal/Keith Glaze Field |
| Baudette International (BDE) | Baudette | MN | Crystal to Baudette International |
| Southwest Michigan Regional (BEH) | Benton Harbor | MI | Crystal to Southwest Michigan Regional |
| Beatrice Municipal (BIE) | Beatrice | NE | Crystal to Beatrice Municipal |
| Bismarck Municipal (BIS) | Bismarck | ND | Crystal to Bismarck Municipal |
| Bemidji Regional (BJI) | Bemidji | MN | Crystal to Bemidji Regional |
| Brookings Regional (BKX) | Brookings | SD | Crystal to Brookings Regional |
| Central Illinois Regional at Bloomington Normal (BMI) | Bloomington | IL | Crystal to Central Illinois Regional at Bloomington Normal |
| Boone Municipal (BNW) | Boone | IA | Crystal to Boone Municipal |
| Brainerd Lakes Regional (BRD) | Brainerd | MN | Crystal to Brainerd Lakes Regional |
| Southeast Iowa Regional (BRL) | Burlington | IA | Crystal to Southeast Iowa Regional |
| Cram Field (BUB) | Burwell | NE | Crystal to Cram Field |
| Wexford County (CAD) | Cadillac | MI | Crystal to Wexford County |
| Council Bluffs Municipal (CBF) | Council Bluffs | IA | Crystal to Council Bluffs Municipal |
| Northeast Iowa Regional (CCY) | Charles City | IA | Crystal to Northeast Iowa Regional |
| The Eastern Iowa (CID) | Cedar Rapids | IA | Crystal to The Eastern Iowa |
| Arthur N Neu (CIN) | Carroll | IA | Crystal to Arthur N Neu |
| Crookston Municipal Kirkwood Field (CKN) | Crookston | MN | Crystal to Crookston Municipal Kirkwood Field |
| Clintonville Municipal (CLI) | Clintonville | WI | Crystal to Clintonville Municipal |
| Houghton County Memorial (CMX) | Hancock | MI | Crystal to Houghton County Memorial |
| Sparta/Fort Mccoy (CMY) | Sparta | WI | Crystal to Sparta/Fort Mccoy |
| Creston Municipal (CSQ) | Creston | IA | Crystal to Creston Municipal |
| Canton Municipal (CTK) | Canton | SD | Crystal to Canton Municipal |
| Central Wisconsin (CWA) | Mosinee | WI | Crystal to Central Wisconsin |
| Clinton Municipal (CWI) | Clinton | IA | Crystal to Clinton Municipal |
| Dubuque Regional (DBQ) | Dubuque | IA | Crystal to Dubuque Regional |
| Decorah Municipal (DEH) | Decorah | IA | Crystal to Decorah Municipal |
| Duluth International (DLH) | Duluth | MN | Crystal to Duluth International |
| Denison Municipal (DNS) | Denison | IA | Crystal to Denison Municipal |
| Dupage (DPA) | Chicago | IL | Crystal to Dupage |
| Des Moines International (DSM) | Des Moines | IA | Crystal to Des Moines International |
| Detroit Lakes-Wething Field (DTL) | Detroit Lakes | MN | Crystal to Detroit Lakes-Wething Field |
| Devils Lake Regional (DVL) | Devils Lake | ND | Crystal to Devils Lake Regional |
| Davenport Municipal (DVN) | Davenport | IA | Crystal to Davenport Municipal |
| Chippewa Valley Regional (EAU) | Eau Claire | WI | Crystal to Chippewa Valley Regional |
| Webster City Municipal (EBS) | Webster City | IA | Crystal to Webster City Municipal |
| Jefferson Municipal (EFW) | Jefferson | IA | Crystal to Jefferson Municipal |
| Eagle River Union (EGV) | Eagle River | WI | Crystal to Eagle River Union |
| Kenosha Regional (ENW) | Kenosha | WI | Crystal to Kenosha Regional |
| Keokuk Municipal (EOK) | Keokuk | IA | Crystal to Keokuk Municipal |
| Delta County (ESC) | Escanaba | MI | Crystal to Delta County |
| Estherville Municipal (EST) | Estherville | IA | Crystal to Estherville Municipal |
| West Bend Municipal (ETB) | West Bend | WI | Crystal to West Bend Municipal |
| Eveleth-Virginia Municipal (EVM) | Eveleth | MN | Crystal to Eveleth-Virginia Municipal |
| Hector International Fargo (FAR) | Fargo | ND | Crystal to Hector International Fargo |
| Faribault Municipal (FBL) | Faribault | MN | Crystal to Faribault Municipal |
| Fairbury Municipal (FBY) | Fairbury | NE | Crystal to Fairbury Municipal |
| Albertus (FEP) | Freeport | IL | Crystal to Albertus |
| Fremont Municipal (FET) | Fremont | NE | Crystal to Fremont Municipal |
| Fairfield Municipal (FFL) | Fairfield | IA | Crystal to Fairfield Municipal |
| Fergus Falls Municipal-Einar Mickelson Field (FFM) | Fergus Falls | MN | Crystal to Fergus Falls Municipal-Einar Mickelson Field |
| Fond Du Lac County (FLD) | Fond Du Lac | WI | Crystal to Fond Du Lac County |
| Fort Madison Municipal (FMS) | Fort Madison | IA | Crystal to Fort Madison Municipal |
| Fort Dodge Regional (FOD) | Fort Dodge | IA | Crystal to Fort Dodge Regional |
| Fairmont Municipal (FRM) | Fairmont | MN | Crystal to Fairmont Municipal |
| Sioux Falls Regional, Joe Foss Field (FSD) | Sioux Falls | SD | Crystal to Sioux Falls Regional, Joe Foss Field |
| Forest City Municipal (FXY) | Forest City | IA | Crystal to Forest City Municipal |
| Galesburg Municipal (GBG) | Galesburg | IL | Crystal to Galesburg Municipal |
| Grand Forks International (GFK) | Grand Forks | ND | Crystal to Grand Forks International |
| Grand Rapids/Itasca County-Gordon Newstrom Field (GPZ) | Grand Rapids | MN | Crystal to Grand Rapids/Itasca County-Gordon Newstrom Field |
| Austin Straubel International (GRB) | Green Bay | WI | Crystal to Austin Straubel International |
| Central Nebraska Regional (GRI) | Grand Island | NE | Crystal to Central Nebraska Regional |
| Grand Marais/Cook County (GRM) | Grand Marais | MN | Crystal to Grand Marais/Cook County |
| Grantsburg Muni (GTG) | Grantsburg | WI | Crystal to Grantsburg Muni |
| Gary/Chicago International (GYY) | GARY | IN | Crystal to Gary/Chicago International |
| Range Regional (HIB) | Hibbing | MN | Crystal to Range Regional |
| Park Township (HLM) | Holland | MI | Crystal to Park Township |
| Huron Regional (HON) | Huron | SD | Crystal to Huron Regional |
| Hampton Municipal (HPT) | Hampton | IA | Crystal to Hampton Municipal |
| Hastings Municipal (HSI) | Hastings | NE | Crystal to Hastings Municipal |
| Humboldt Municipal (HUD) | Humboldt | IA | Crystal to Humboldt Municipal |
| Sawyer County (HYR) | Hayward | WI | Crystal to Sawyer County |
| Schenck Field (ICL) | Clarinda | IA | Crystal to Schenck Field |
| Ida Grove Municipal (IDG) | Ida Grove | IA | Crystal to Ida Grove Municipal |
| Iowa Falls Municipal (IFA) | Iowa Falls | IA | Crystal to Iowa Falls Municipal |
| Jacksonville Municipal (IJX) | Jacksonville | IL | Crystal to Jacksonville Municipal |
| Greater Kankakee (IKK) | Kankakee | IL | Crystal to Greater Kankakee |
| Willmar Municipal/John L Rice Field (ILL) | Willmar | MN | Crystal to Willmar Municipal/John L Rice Field |
| Ford (IMT) | Iron Mountain | MI | Crystal to Ford |
| Falls Intl-Einarson Field (INL) | International Falls | MN | Crystal to Falls Intl-Einarson Field |
| Iowa City Municipal (IOW) | Iowa City | IA | Crystal to Iowa City Municipal |
| Kirksville Regional (IRK) | Kirksville | MO | Crystal to Kirksville Regional |
| Schoolcraft County (ISQ) | Manistique | MI | Crystal to Schoolcraft County |
| Alexander Field South Wood County (ISW) | Wisconsin Rapids | WI | Crystal to Alexander Field South Wood County |
| Gogebic-Iron County (IWD) | Ironwood | MI | Crystal to Gogebic-Iron County |
| Morden (JA3) | Morden | MB | Crystal to Morden |
| Steinbach (JB3) | Steinbach | MB | Crystal to Steinbach |
| Altona Municipal (JL6) | Altona | MB | Crystal to Altona Municipal |
| Jamestown Regional (JMS) | Jamestown | ND | Crystal to Jamestown Regional |
| Joliet Regional Airport (JOT) | Joliet | IL | Crystal to Joliet Regional Airport |
| Souther Wisconsin Regional (JVL) | Janesville | WI | Crystal to Souther Wisconsin Regional |
| Mason County (LDM) | Ludington | MI | Crystal to Mason County |
| Lincoln Municipal (LNK) | Lincoln | NE | Crystal to Lincoln Municipal |
| Tri-County Regional (LNR) | Lone Rock | WI | Crystal to Tri-County Regional |
| Lewis University Chicago Romeoville (LOT) | Chicago/Romeoville | IL | Crystal to Lewis University Chicago Romeoville |
| Le Mars Municipal (LRJ) | Le Mars | IA | Crystal to Le Mars Municipal |
| La Crosse Regional (LSE) | La Crosse | WI | Crystal to La Crosse Regional |
| Ely Municipal (LYU) | Ely | MN | Crystal to Ely Municipal |
| Quentin Aanenson Field (LYV) | Luverne | MN | Crystal to Quentin Aanenson Field |
| Mobridge Municipal (MBG) | Mobridge | SD | Crystal to Mobridge Municipal |
| Manistee County-Blacker (MBL) | Manistee | MI | Crystal to Manistee County-Blacker |
| Omar N Bradley (MBY) | Moberly | MO | Crystal to Omar N Bradley |
| Mason City Municipal (MCW) | Mason City | IA | Crystal to Mason City Municipal |
| Taylor County (MDF) | Medford | WI | Crystal to Taylor County |
| Chicago Midway International (MDW) | Chicago | IL | Crystal to Chicago Midway International |
| Marshfield Municipal (MFI) | Marshfield | WI | Crystal to Marshfield Municipal |
| Michigan City Municipal-Phillips Field (MGC) | Michigan City | IN | Crystal to Michigan City Municipal-Phillips Field |
| Mitchell Municipal (MHE) | Mitchell | SD | Crystal to Mitchell Municipal |
| Omaha Millard (MIQ) | Omaha | NE | Crystal to Omaha Millard |
| Marshalltown Municipal (MIW) | Marshalltown | IA | Crystal to Marshalltown Municipal |
| Jackson Municipal (MJQ) | Jackson | MN | Crystal to Jackson Municipal |
| Milwaukee General Mitchell International (MKE) | Milwaukee | WI | Crystal to Milwaukee General Mitchell International |
| Muskegon County (MKG) | Muskegon | MI | Crystal to Muskegon County |
| Mankato Regional (MKT) | Mankato | MN | Crystal to Mankato Regional |
| Quad City International (MLI) | Moline | IL | Crystal to Quad City International |
| Southwest Minnesota Regional Marshall/Ryan Field (MML) | Marshall | MN | Crystal to Southwest Minnesota Regional Marshall/Ryan Field |
| Menominee-Marinette Twin County (MNM) | Menominee | MI | Crystal to Menominee-Marinette Twin County |
| Morris Municipal/Charlie Schmidt Field (MOX) | Morris | MN | Crystal to Morris Municipal/Charlie Schmidt Field |
| Mount Pleasant Municipal (MPZ) | Mount Pleasant | IA | Crystal to Mount Pleasant Municipal |
| Macomb Municipal (MQB) | Macomb | IL | Crystal to Macomb Municipal |
| Sawyer International (MQT) | Marquette | MI | Crystal to Sawyer International |
| Truax Field/Dane County Regional (MSN) | Madison | WI | Crystal to Truax Field/Dane County Regional |
| Manitowoc County (MTW) | Manitowoc | WI | Crystal to Manitowoc County |
| Muscatine Municipal (MUT) | Muscatine | IA | Crystal to Muscatine Municipal |
| Montevideo-Chippewa County (MVE) | Montevideo | MN | Crystal to Montevideo-Chippewa County |
| Lawrence J Timmerman (MWC) | Milwaukee | WI | Crystal to Lawrence J Timmerman |
| Windom Municipal (MWM) | Windom | MN | Crystal to Windom Municipal |
| Monticello Regional (MXO) | Monticello | IA | Crystal to Monticello Regional |
| Slayton Municipal (NSL) | Slayton | MN | Crystal to Slayton Municipal |
| Norfolk Regional/Karl Stefan Memorial Field (OFK) | Norfolk | NE | Crystal to Norfolk Regional/Karl Stefan Memorial Field |
| Columbus Municipal (OLU) | Columbus | NE | Crystal to Columbus Municipal |
| Eppley Airfield (OMA) | Omaha | NE | Crystal to Eppley Airfield |
| Winona Municipal-Max Conrad Field (ONA) | Winona | MN | Crystal to Winona Municipal-Max Conrad Field |
| The O'neill Municipal-John L Baker Field (ONL) | O'neill | NE | Crystal to The O'neill Municipal-John L Baker Field |
| Oskaloosa Municipal (OOA) | Oskaloosa | IA | Crystal to Oskaloosa Municipal |
| Chicago O'hare International (ORD) | Chicago | IL | Crystal to Chicago O'hare International |
| Wittman Regional (OSH) | Oshkosh | WI | Crystal to Wittman Regional |
| Worthington Municipal (OTG) | Worthington | MN | Crystal to Worthington Municipal |
| Ottumwa Regional (OTM) | Ottumwa | IA | Crystal to Ottumwa Regional |
| Owatonna Degner Regional (OWA) | Owatonna | MN | Crystal to Owatonna Degner Regional |
| Prairie Du Chien Municipal (PCD) | Prairie Duchien | WI | Crystal to Prairie Du Chien Municipal |
| Gen Wayne A Downing Peoria International (PIA) | Peoria | IL | Crystal to Gen Wayne A Downing Peoria International |
| Pierre Regional (PIR) | Pierre | SD | Crystal to Pierre Regional |
| Park Rapids Municipal-Konshok Field (PKD) | Park Rapids | MN | Crystal to Park Rapids Municipal-Konshok Field |
| Park Falls Municipal (PKF) | Park Falls | WI | Crystal to Park Falls Municipal |
| Pembina Municipal (PMB) | Pembina | ND | Crystal to Pembina Municipal |
| Pocahontas Municipal (POH) | Pocahontas | IA | Crystal to Pocahontas Municipal |
| Perry Municipal (PRO) | Perry | IA | Crystal to Perry Municipal |
| Prentice Municipal (PRW) | Prentice | WI | Crystal to Prentice Municipal |
| Chicago Executive (PWK) | Chicago | IL | Crystal to Chicago Executive |
| Batten International (RAC) | Racine | WI | Crystal to Batten International |
| Nartron Field (RCT) | Reed City | MI | Crystal to Nartron Field |
| Chicago/Rockford International (RFD) | Rockford | IL | Crystal to Chicago/Rockford International |
| Rhinelander Oneida County (RHI) | Rhinelander | WI | Crystal to Rhinelander Oneida County |
| Rice Lake Regional - Carl's Field (RIE) | Rice Lake | WI | Crystal to Rice Lake Regional - Carl's Field |
| Roseau Municipal/Rudy Billberg Field (ROX) | Roseau | MN | Crystal to Roseau Municipal/Rudy Billberg Field |
| Merrill Municipal (RRL) | Merrill | WI | Crystal to Merrill Municipal |
| Warroad International Memorial (RRT) | Warroad | MN | Crystal to Warroad International Memorial |
| Rochester International (RST) | Rochester | MN | Crystal to Rochester International |
| Spirit Lake Municipal (RTL) | Spirit Lake | IA | Crystal to Spirit Lake Municipal |
| Redwood Falls Municipal (RWF) | Redwood Falls | MN | Crystal to Redwood Falls Municipal |
| Sheboygan County Memorial (SBM) | Sheboygan | WI | Crystal to Sheboygan County Memorial |
| Scribner State (SCB) | Scribner | NE | Crystal to Scribner State |
| Storm Lake Municipal (SLB) | Storm Lake | IA | Crystal to Storm Lake Municipal |
| Spencer Municipal/Northwest Iowa Regional (SPW) | Spencer | IA | Crystal to Spencer Municipal/Northwest Iowa Regional |
| Whiteside Co-Jos H Bittorf Field (SQI) | Sterling/Rock Falls | IL | Crystal to Whiteside Co-Jos H Bittorf Field |
| St Cloud Regional (STC) | St Cloud | MN | Crystal to St Cloud Regional |
| Stevens Point Municipal (STE) | Stevens Point | WI | Crystal to Stevens Point Municipal |
| Rosecrans Memorial (STJ) | St Joseph | MO | Crystal to Rosecrans Memorial |
| Door County Cherryland (SUE) | Sturgeon Bay | WI | Crystal to Door County Cherryland |
| Richard I Bong Memorial (SUW) | Superior | WI | Crystal to Richard I Bong Memorial |
| Sioux Gateway/Col Bud Day Field (SUX) | Sioux City | IA | Crystal to Sioux Gateway/Col Bud Day Field |
| Newton Municipal (TNU) | Newton | IA | Crystal to Newton Municipal |
| Trenton Municipal (TRX) | Trenton | MO | Crystal to Trenton Municipal |
| Britton Municipal (TTO) | Britton | SD | Crystal to Britton Municipal |
| Cherry Capital (TVC) | Traverse City | MI | Crystal to Cherry Capital |
| Thief River Falls Regional (TVF) | Thief River Falls | MN | Crystal to Thief River Falls Regional |
| Waukesha County (UES) | Waukesha | WI | Crystal to Waukesha County |
| Chicago/Waukegan Regional (UGN) | Chicago | IL | Crystal to Chicago/Waukegan Regional |
| Baldwin Field/Quincy Regional (UIN) | Quincy | IL | Crystal to Baldwin Field/Quincy Regional |
| Waukon Municipal Airport (UKN) | Waukon | IA | Crystal to Waukon Municipal Airport |
| New Ulm Municipal (ULM) | New Ulm | MN | Crystal to New Ulm Municipal |
| Dodge County (UNU) | Juneau | WI | Crystal to Dodge County |
| Porter County Regional (VPZ) | Valparaiso | IN | Crystal to Porter County Regional |
| Miller Field (VTN) | Valentine | NE | Crystal to Miller Field |
| Walter A Duncan Field/Illinois Valley Regional (VYS) | Peru | IL | Crystal to Walter A Duncan Field/Illinois Valley Regional |
| Harry Stern (WAH) | Wahpeton | ND | Crystal to Harry Stern |
| Roben-Hood (WBR) | Big Rapids | MI | Crystal to Roben-Hood |
| Grand Geneva Resort (XES) | Lake Geneva | WI | Crystal to Grand Geneva Resort |
| Madison Municipal (XMD) | Madison | SD | Crystal to Madison Municipal |
| Fort Frances Municipal (YAG) | Fort Frances | ON | Crystal to Fort Frances Municipal |
| Winnipeg/St Andrews (YAV) | Winnipeg | MB | Crystal to Winnipeg/St Andrews |
| Dryden Regional (YHD) | Dryden | ON | Crystal to Dryden Regional |
| Atikokan Municipal (YIB) | Atikokan | ON | Crystal to Atikokan Municipal |
| Chan Gurney Municipal (YKN) | Yankton | SD | Crystal to Chan Gurney Municipal |
| Portage La Prairie/Southport (YPG) | Portage La Prairie | MB | Crystal to Portage La Prairie/Southport |
| Kenora (YQK) | Kenora | ON | Crystal to Kenora |
| Thunder Bay (YQT) | Thunder Bay | ON | Crystal to Thunder Bay |
| James Armstrong Richardson/Winnipeg International (YWG) | Winnipeg | MB | Crystal to James Armstrong Richardson/Winnipeg International |
| Sioux Lookout (YXL) | Sioux Lookout | ON | Crystal to Sioux Lookout |
| Ignace Municipal (ZUC) | Ignace | ON | Crystal to Ignace Municipal |
