CHANGJIN JOURNAL  05.15.10  Chapter 75

The Changjin Journal is designed to disseminate and solicit information on the Chosin campaign. Comments and brief essays are invited. Subject matter will be limited to history of the Chosin campaign, as well as past or present interpretation of that history. See End Notes for distribution and other notices.

Colonel George A. Rasula, USA-Ret., Chosin Historian

Byron Sims, Contributing Editor

We continue the 2006-10 series of the Changjin Journal addressing the Chosin campaign based on the Aide-Memoire of Maj. Gen. O.P. Smith, commander of the 1st Marine Division, providing the reader with copies of his memoire within which we offer comments from various sources that relate to the topic at hand. In the last issue (CJ 11.15.09) we addressed the Defense of Hagaru-ri.

IN THIS ISSUE we provide initial directives of X Corps regarding protection of the MSR, regrouping of units in the Chosin Reservoir area, and activities at and south of Chinhung-ni where the Chinese had been attempting a deep envelopment. This section contains information about unit dispositions and combat actions that are not included in most contemporary publications about the Chosin campaign.

Sections (Š) and page numbers [Š] are included for reference purposes. Bold typeface is used for emphasis, with editor's comments in [brackets]. Readers are reminded that these documents were not written at the time of the action, but finalized after Maj. Gen. Smith left Korea. His primary sources were unit reports and briefings by commanders and staff, and his own personal diary. However, they do reflect his view of what happened and how he wished them to be remembered.

Ops (262/264) 888-889 & 907-914
Map 1978 Chosin south 1-250.jpg
This 1:250,000 topographic map dated 1978 is offered to provide readers an appreciation for the terrain. The name of the town CHANGJIN (Hagaru-ri) south of the reservoir and the blue airfield symbol did not exist in 1950. A study of the mountain ridges and valleys will highlight problems that existed at the time for what was then believed to be normal military operations. As one can see, the main axis of land communications is related to the reservoir system and travels north on the east side of the Chosin Reservoir following the Changjin River, eventually turning west to Kanggye and the Yalu River. The mountain range in the northwest quadrant of this map is the area through which the 1MarDiv was ordered to attack 27 November to assist the Eighth Army that, at the time, the nearest unit was more than 80 miles to the southwest. The fury of winter had yet to arrive and X Corps didn't have any snowplows. – GAR

(262) Initial Directives of the X Corps Regarding Protection of the MSR and Regroupment in the Chosin Reservoir Area

   On 28 November, X Corps OI was received by the Division. This OI altered the boundary in the X Corps zone, placing Majon-dong in the zone of the 3d Infantry Division, and assigning it a mission of protecting the MSR in the vicinity of Majon-dong and operating along the Majon-dong - Hagaru-ri axis. On this date A Co 1st Tank Bn was at Majon-dong.

     X Corps order Cite 13376 was received by the Division at 1745, 29 November, and provided for all elements of the X Corps to pass to the operational control of the 1st Marine Division during movement along the X Corps MSR between Koto-ri and Hagaru-ri.

        Confirming a telephone call by radio link late in the day. Another X Corps order was received at 2205, 29 November, directing the Division to continue to protect the MSR in the area occupied by the 1st Marine Regiment until relieved by elements of the 7th Inf Div.
[This instruction was apparently related to other Corps plans to use elements of the 7th Inf Div (RCT 17 or 32) which had been withdrawing to form the
Hungnam perimeter, plans which never matured due to the changing tactical situation. – GAR]

        At 2218, 29 November, X Corps OI 19 was received by the Division. This OI read as follows: "Cite 13409 X Corps OI Number 19 follows in three parts. Part 1: Effective at once all elms 7th Inf Div in Koto-ri (CV5560), Hagaru-ri (C V5171), Chosin Reservoir area are attached to 1st MarDiv. Part 2: 1st MarDiv redeploy one RCT without delay from Yudam-ni (CV4182) area to Hagaru-ri area, gain contact with elms 7th InfDiv east of Chosin Reservoir; coordinate all forces in and north of Hagaru-ri in a perimeter defense based on Hagaru-ri; open and secure Hagaru-ri - Koto-ri MSR. Part 3: X Corps coordinates movement to Koto-ri of elms 7th Inf Div now south Koto-ri."

[Although the foregoing X Corps Operations Instruction attaches all Army units at Koto-ri and north thereof to 1MarDiv, we are unable to find instructions to or communication with RCT-31 units east of Chosin providing guidance regarding this attachment. For those not familiar with the term "attachment," RCT-31 assumed the same position in the command structure as the Marine regiments. – GAR]

X Corps OpO #8 issued on 30 November was received by the Division at 1400 that date. This order stated the Corps mission to be "maintaining contact with the enemy to the maximum capability consistent with cohesive action, oriented to the Hamhung-Hungnam base of operations". The mission assigned the 1st Marine Division was to operate against the enemy in zone, withdrawing elements north and northwest of Hagaru-ri to the Hagaru-ri area, and to secure the Sudong-Hagaru-ri MSR. (It might be pointed out that the Division had no difficulty at this point in the operation of "maintaining contact with the enemy to the maximum capability consistent with cohesive action".)
[It is important to note that Gen. Smith was given mission of withdrawing elements north and northwest of Hagaru-ri, yet at no time during 30 Nov or 1 Dec did he initiate communications with or issue withdrawal orders to the RCT-31 elements (
LTC Don Faith) north of Hagaru-ri. However, he did initiate action on 30 Nov to withdraw the 31st Tank Company and other elements from Hudong-ni to reinforce defenses at Hagaru-ri, thereby sealing the fate of "Task Force Faith." –GAR]

Click on the map above for a larger image
Map #27 from The Chosin Chronology: Battle of the Changjin Reservoir, 1950, copyright © 2006, George A. Rasula. This map shows the situation faced by MG Smith on the night of 28-29 November when he was receiving orders and planning the breakout. Note the road from Yudam-ni south to Sachang-ni defended by 1/7 and 2/7 Infantry of the 3d Division; noting also that a road (trail) to the east provides Chinese access into Smith's left flank, south of the 1/1 Marines at Chinhung-ni. Bear in mind when you read the following that Chinese units arriving in this area were armed and equipped with that which individual soldiers carried, or may have carried on a few draft animals. This was mountainous terrain traversed by woodsmen carrying timber on ox-drawn carts or sleds. – GAR



[OPS (263) 890-906 at this point in the Aide-Memoire contains “Attack On, Overrunning and Rescue of Army Task Force East of the Chosin Reservoir,” previously published in Changjin Journal 06.30.08, Chapter 71.]

OPS (264) 907-914

(264) Activities at Chinhung-ni and along the MSR to the South thereof

Preliminary Operations
    On 22 November, as part of the move to have RCT-1 take over protection of the MSR between Chinhung-ni and Hagaru-ri, B Co 1/1Marines moves from Chigyong to Chinhung-ni and relieved the 3/5Marines threat to allow that battalion to move to Hagaru-ri. On 23 November, the remainder of the 1/1Marines moved to Chinhung-ni
  From 23 to 27 November, the 1st Bn patrolled aggressively in the Chunghung-ni area without enemy contact except for a light probing attack on the night of 26 November. On 27 November, artillery harassing fires were called down on a group of 300 horsemen who were reported moving toward the battalion's positions. There were no observed results. At 1900, 27 November, the western sector of the perimeter was attacked by an estimated enemy platoon. The attack was repulsed. There was also a light patrol contact on 28 November.

Garrison of Chinhung-ni
On the night of 27-28 November, when the CCF launched their counteroffensive in the Yudam-ni area, the garrison of Chinhung-ni was as shown below. Strengths of units are estimated. [Abbreviated by editor]

1/1 Marines and attached small units
F Btry 2/11 Marine Artillery   
B 1st Engr Bn (-)

D 1st Engr Bn (-)

Total           1,689

        On the MSR south of Chinhung-ni there were still a considerable number of Marines who were involved in the protection of the MSR in the vicinity of the towns where they were located.

Majon-Dong       A/1st Tank Bn           132

Ssangbong-ni    C/1st 4.5 Rocket Bn     80

Soyang-ni           Tank units                  525

                                           Total           737

Events of 29 and 30 November

    At 1730, 29 November, the CCF ambushed a six-truck convoy about 3 miles south of Koto-ri. Thereafter, the CCF began to close in on the MSR between Chinhung-ni and Koto-ri, and, after 1 December, the road was completely blocked. On 29 November, the 1/1 Marines at Chinhung-ni had received a probing attack. This coupled with reports from refugees indicated that there was a considerable enemy build-up west of Chinhung-ni. The battalion commander decided to launch a reconnaissance in force in that direction the following day.

  At 0730, 30 November, the 1/1 Marines dispatched a recon in force to the west of Chinhung-ni with the mission of attacking and destroying enemy forces, which, according to reports, were in the vicinity of TA 5149QR, about 2 _ miles west of Chinhung-ni. The force consisted of A and B companies, reinforced. By 1000, the recon in force had engaged and overrun strong enemy outposts at TA 5448A, about 1500 yards west of Chinhung-ni, and had developed the main enemy defensive positions. Moving along the ridgelines the recon force enveloped both flanks of the enemy position. Covered by artillery, 4.2" mortars, seven VMF planes, and fire from both flanks, the recon force launched an attack against the enemy force which was concentrated near the village in the valley floor. Tactical surprise was accomplished, and the CCF, in battalion strength, with numerous pack horses, was completely routed. In their retreat, the enemy abandoned equipment and dead but retained their horses. The pursuit was pressed until 1630, at which time the recon force broke contact. The enemy withdrew up the valley to the northwest under constant attack by friendly aircraft. The Chinese troops encountered were well clothed in green and white reversible overcoats and were equipped with numerous automatic weapons, mortars and demolition kits. The recon force encountered 28 enemy dead and estimated it had killed 150. The force returned to the perimeter of Chinhung-ni at 1740.

[Although not addressed, the foregoing description of a combat action does expose the limitations of the enemy: a
CCF battalion had marched at night by foot and pack animals almost 100 miles from the Yalu River to accomplish an unidentified mission, probably deep envelopment. Were the demolition kits related to the destruction of the bridge at the Gatehouse in the Funchilin Pass? Did anyone see this as a red flag, alerting commanders as to the vulnerability of the bridge? We also note that the recon force broke contact with the enemy and returned to home base, once again leaving the countryside to the enemy during the long hours of darkness. Since no friendly casualties were reported, the large number of Chinese killed must have come from friendly artillery and air strikes. – GAR]

Map 1-50 Funchilin Pass.jpg
Readers are reminded that map coordinates are read "right and up." The critical bridge and gatehouse in the pass is located in grid square 5554, a 1,000 meter grid; more accurately to 100 meters 552542. Note "Changjin Power Plant No 1" downhill at 552528 where water from the large pipes originating at the gatehouse flow to power the turbines. An amazing feat of engineering by the Japanese because the water entering the gatehouse arrives from an underground aqueduct all the way from the Chosin Reservoir (about 25 kilometers/15.5 miles); there, reservoir surface water flows naturally northward to the Yalu River.

From a tactical point of view, this pass could have been a barrier from either direction. Note that the contour lines on this map are 20 meters (65 feet), making the slope west (left) of the road almost a cliff. Properly used, those switchbacks of the road could have delayed the Marine Division's northward movement far longer than it had; from the Chinese point of view, they didn't have the military resources and time to create effective fire-blocks. This limitation in resources continued because of the effective defensive battles fought by the Marines at Yudam-ni and Army units north of Hagaru-ri, backed up by air support using the seldom mentioned scorched-earth policy that existed at the time. The policy of living off the land as they did in China was not possible in the desolate area of northeast Korea, especially when Father Winter seized control. – GAR

Events of 1 to 7 December

     On 1 December, the 1/1Marines continued patrolling to the north and northwest without enemy contact.

    On 2 December, the 1/1Marines sent three recon patrols to the north and west. Patrol No. 1, six men, scouted in the vicinity of TA 5349, 1 _ miles west of Chinhung-ni. Five enemy were observed using civilians and ox-carts to move equipment. Patrol No. 2, consisting of one rifle platoon, moved north along the railroad to TA 5654, three miles north of Chinhung-ni, encountering no enemy. Patrol No. 3, consisting of one squad of infantry and an artillery FO Team attached, proceeded north on he MSR in three jeeps and one 2 ½-ton truck to TA 5455, three miles south of Koto-ri, to determine the strength and disposition of the enemy forces blocking the MSR. The Battalion Commander accompanied this patrol. The passage of the patrol was uninterrupted. At the last bend in the road just before reaching the point where the penstocks passed under the road and descended to the power plant in the valley below, the patrol was stopped and the vehicles were turned around so that they faced down-canyon. The patrol continued on foot and passed the bridge at the penstocks without seeing any signs of life. But, after it made the turn beyond the bridge and scanned the ridges northward to the left of the road, a considerable number of enemy troops could be seen moving freely about the ridges. The Battalion Commander could not resist the temptation to bring artillery fire to bear on this lucrative target. The artillery FO climbed to a point where he could observe and artillery fire was brought down with good effect. Manifestly, the patrol could not tarry in the area very long as the enemy was aroused. The members of the patrol double-timed to their vehicles and took off down the road. The patrol missed interception by a CCF company by around 150 yards as it passed the point where the cableway crossed the MSR. A radio message was sent to the patrol which had moved up the railroad directing it to withdraw. By 1530, the patrols had returned to Chinhung-ni.

[The word "penstocks" was used to define the large pipes which was controlled by the penstocks (control gates) in the gatehouse. The enemy positions in that area had been observed in early November by the 7th Marines when they first moved north into the
Funchilin Pass area. The precise identification of these positions would have been ideal for artillery interdiction, especially before and during the attack north from Chinhung-ni by the 1/1 Marines on 8-9 Dec. – GAR]

      On 3 December, without the knowledge of the CO 1/1Marines, one squad of the 50th AAA(AW) Bn, which had arrived at Chinhung-ni in advance of its parent unit, attempted a recon of the road to Koto-ri. The Division had requested the assignment of the 50th AAA to the 1st Marines at Koto-ri. The detachment of the 50th AAA came under enemy fire at about the point where the cableway passed over the MSR. Two Army men were killed and the Quad 40 was abandoned. The surviving personnel of the recon party returned to Chinhung-ni on foot.
[Correction: A "Quad" (M16) has four 50-caliber guns mounted on a halftrack; a "Dual" (M19) has two 40mm guns mounted on a tank chassis. – GAR]

        For a brief period on 3 December, the enemy moved on to the MSR south of Chinhung-ni in the vicinity of Majon-dong. Supported by machine guns and carrying demolitions the small enemy force succeeded in blowing out a bridge on the MSR. The bridge was repaired by Army engineers during the day.


Map Nightmare Alley Sudong.jpg
[CAPTION] This is a scanned copy of an original map from a member of 1MarDiv who fought the battle by the 7th Marines and named this sector Nightmare Alley. This section of the 1:50,000 map covers Sudong to Majon-dong mentioned below. Due to the rugged terrain, some may have called it Ambush Alley. – GAR

  On 6 December, enemy activity in the Chinhung-ni-Majon-dong area increased, as in three separate but coordinated actions the CCF cut the MSR between these two points. Armed with small arms and automatic weapons, 50 to 70 enemy launched two separate attacks against a detachment of the 1st Engr Bn at Sudong. The first attack at 1000, was driven off when a patrol from the 1/1 Marines at Chinhung-ni arrived to reinforce the engineer detachment. After the patrol withdrew, a second and stronger attack was made and another patrol was dispatched to the aid of the detachment. The enemy was again repulsed and the engineer detachment was moved north to Chinhung-ni.

       At 1100, 6 December, a 14-vehicle Marine convoy was attacked by an estimated 200 enemy halfway between Sudong and Majon-dong. An Army company [of the 3d Infantry Division] moved out from Majon-dong during the afternoon to aid the besieged convoy that was pinned down by enemy fire and was temporarily unable to withdraw. Air later reported that an estimated enemy company was digging in along the high ground just east of the attack site and that the MSR at that point was in enemy hands.

     At Majon-dong, on 6 December, an Army infantry patrol led by a platoon of Marine tanks moved to a point some 2000 yards northwest of Majon-dong where it encountered approximately 400 CCF troops. Moving out without the infantry, the Marine tanks killed an estimated 30 enemy with machine gun fire and dispersed the remainder. During the engagement the enemy unsuccessfully tried to use Molotov cocktails and satchel charges against the Marine tanks. There were no casualties by Marine or Army personnel.

   At 2115, 6 December, the Division, by dispatch to X Corps, requested that the 1/1 Marines at Chinhung-ni be relieved by Task Force DOG (essentially an Army infantry battalion) by 1600, 7 December, in order to permit the 1/1 Marines to attack north in support of the bulk of the Division which was attacking south from Koto-ri on 8 December. The operations of the 1/1 Marines in this role will be covered under "Regroupment and Breakout from Koto-ri".
[For the record, Task Force DOG consisted of:
3d Bn, 7th Infantry, 3ID
   92d AFA (SP) Bn
Co A, 73d Engr (C) Bn
   Platoon, Co A, 10th Engr (C) Bn
3d Plat, 3d Recon Company
   52d Trans Truck Bn
   Det, 3d AAA (AW) SP Bn
  Bomb Disposal Det
       Tactical Air Control Party (TACP)
       Det, 3d Signal Co

(264)  [888-914]


The foregoing section of the Aide-Memoire reveals that a few CCF units were operating at the extreme limits of a deep envelopment. We are reminded that Chinese soldiers were operating with the clothing, equipment and supplies that they carried all the way from the crossing of the Yalu River. At this extreme a CCF unit that suffered serious losses had to be replaced by another unit – if available; resupply was not available. As we continue our journey through Chosin history we learn once again that Chinese unit effectiveness continued to be reduced, arriving with but a token force to eventually oppose the American and South Korean units on the Hungnam perimeter.

END CJ 05.15.10

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