Boeing Monomail

Model 200 and 221 Monomail
	Model 200
Role	Airliner
National origin	United States
Manufacturer	Boeing
First flight	6 May 1930
Retired	1933
Status	Retired
Primary user	United Airlines
Number built	1 Model 200 ; 1 Model 221
Developed into	Boeing YB-9

The Boeing Model 200 Monomail was an American mail plane of the early 1930s.

Design and development

The aircraft marked a departure from the traditional biplane configuration for a transport aircraft, instead featuring a single, low set, all metal cantilever wing. Retractable landing gear and a streamlined fuselage added to the aerodynamic efficiency of the aircraft. A single example was constructed for evaluation by both Boeing and the US Army (under the designation Y1C-18) but no mass production ensued, and the aircraft eventually joined Boeing's fleet on the San Francisco-Chicago air mail route from July 1931.

A second version was developed as the Model 221, with a fuselage stretched by 8 inches (20 cm) that sacrificed some of its cargo capacity to carry six passengers in an enclosed cabin; the single pilot, however, sat in an open

United Air Lines' Cheyenne

-Chicago route.

The advanced design of the Monomail was hampered by the lack of suitable

P-26 Peashooter

of the USAAC), respectively.

Variants

Model 200: mailplane (1 built)
Model 221: mailplane with capacity for 6 passengers (1 built)
Model 221A: Model 200 and 221 converted as 8-passenger airliners
Model 231: Planned lengthened version of Model 221, not built.

Operators

United States

Boeing Air Transport
United Air Lines

Specifications (Model 221)

General characteristics

Crew: One pilot
Capacity: 6 passengers
Length: 42 ft 0 in (12.75 m)
Wingspan: 59 ft 0 in (18 m)
Airfoil: Boeing 106
Gross weight: 8,000 lb (3,629 kg)
Powerplant: 1 ×
Pratt & Whitney R-1860 Hornet B radial engine
, 575 hp (428.8 kW)

Propellers: 2-bladed

Performance

Maximum speed: 158 mph (254 km/h, 137 kn)
Cruise speed: 135 mph (217 km/h, 117 kn)
Range: 575 mi (925 km, 500 nmi)
Service ceiling: 14,700 ft (4,480.5 m)

References

Boeing History - Boeing Monomail Transport Retrieved June 17, 2006.
Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions.
World Aircraft Information Files. London: Bright Star Publishing.

v t e Boeing aircraft model numbers
Aircraft	1 2 3 4 5 6 6D/E 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 220 221 222 223 224 225 226 227 228 229 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 276 277 278 279 280 281 282 283 284 285 286 287 288 290 291 292 293 294 295 296 297 298 299 300 302 303 304 305 306 307 308 309 311 312 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 345-2/4/31 346 348 349 350 351 352 353 354 355 356 357 358 359 361 362 363 364 365 366 367 -76 367-80 368 369 370 371 372 373 374 375 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 431 432 433 434 435 436 437 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 479 480 481 482 483 484 485 486 490 493 495 497 498 701 733 739 814 815 818 820 831 844 853-21 953 1041 1044 1046 1074 1080 2000 2020 707 -020 717 (I) -100/146/148/166 717 (II) 720 727 737 -235 Classic Next Generation -700W MAX 747 SP -2G4B -400 -4G4F -8 757 -2G4 767 777 X 787 2707
Turbine engines	8C 500 502 520 550
Missiles	600 601 602 621 624 631 641
Vessels	929
Other	Boeing Customer Codes

v t e United States military transport aircraft designations, Army/Air Force and Tri-Service systems
Army/Air Force sequence (1925-1962)	C-1 C-2 C-3 C-4 C-5 C-6 C-7 C-8 C-9 C-10 C-11 C-12 C-13¹ C-14 C-15 C-16 C-17 C-18 C-19 C-20 C-21 C-22 C-23 C-24 C-25 C-26 C-27 C-28 C-29 C-30 C-31 C-32 C-33 C-34 C-35 C-36 C-37 C-38 C-39 C-40 C-41 C-41A C-42 C-43 C-44 C-45 C-46 C-47 C-47F C-47T AC-47 C-48 C-49 C-50 C-51 C-52 C-53 C-54 C-55 C-56 C-57 C-58 C-59 C-60 C-61 C-62 C-63 C-64 C-65 C-66 C-67 C-68 C-69 C-70 C-70B C-71 C-72 C-73 C-74 C-75 C-76 C-77 C-77B–D C-78 C-79 C-80 C-81 C-82 C-83 C-83A C-83B C-84 C-85 C-86 C-87 C-88 C-89 C-90 C-91 C-92 C-93 C-94 C-95 C-96 C-97 KC-97 C-98 C-99 C-100 C-101 C-102 C-103 C-104 C-105 C-106 C-107 C-108 C-109 C-110 C-111 C-112 C-113 C-114 C-115 C-116 C-117 C-117D C-118 C-119 AC-119 C-120 C-121 C-121F EC-121 C-122 C-123 C-123A C-124 C-125 C-126 C-127² C-127 (I) C-127 (II) C-128 C-129 C-130 C-130J AC-130 DC-130 EC-130/H HC-130 KC-130 LC-130 MC-130 WC-130 C-131 NC-131H C-132 C-133 C-134 C-135 KC-135 C-136 C-137² YC-137 (I) YC-137 (II) C-137 C-138¹ C-139¹ C-140 C-141 C-142
Tri-service sequence (1962-present)	C-1 C-2 C-3 C-4 C-5 C-6 C-7² C-7 RC-7 C-8 C-9 C-10² C-10 KC-10 C-11 C-12 RC-12 C-13¹ C-14 C-15 C-16¹ C-17 C-18 C-19 C-20² C-20A–D C-20F–J C-21 C-22 C-23 C-24 C-25 C-26 C-27 C-27J C-28 C-29 C-30¹ C-31 C-32 C-33 C-34¹ C-35 C-36³ C-37 C-37B C-38 C-39¹ C-40 C-41 C-42¹ C-43¹ C-44¹ C-45 C-46
Revived original sequence (2005-present)	C-143 C-144 C-145 C-146 C-147
Non-sequential designations	C-767 C-767B C-880
Related designations	CT-39 CT-43 CV-2 CV-7
¹ Not assigned • ² Assigned to multiple types • ³ Unconfirmed