Mercury Redstone 4 Mission Log

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"I was lying there, minding my own business, when I heard a dull thud."

This photo shows a view from the helicopter with call sign "Hunt Club 1" during its attempt to recover Liberty Bell 7. Jim Lewis, who was the pilot of the helicopter, autographed and inscribed the photo.
Photo Credit: NASA

View Of Liberty Bell 7 From Recovery Helicopter

The second manned flight in the Mercury program was also a suborbital flight. Virgil Ivan (Gus) Grissom was the commander.

Grissom named his spacecraft Liberty Bell 7. Calling to mind the original Liberty Bell in Philadelphia, there was even a crack painted on the side of the spacecraft. Like its namesake, the spacecraft would also develop a serious flaw during the mission.

MR-4 was launched on July 21, 1961. At the moment of liftoff, the astronaut in the blockhouse responsible for communication with the spacecraft announced, "Liftoff." Grissom responded, "Ah, Roger. This is Liberty Bell 7. The clock is operating." The Capsule Communicator in the Mercury Control Center then added, "Loud and clear, José, don't cry too much." Grissom responded, "Oke-doke." Later Grissom radioed, "Okay, it is a nice ride up to now."

At 1 minute and 56 seconds into the flight Grissom reported his status, "Everything is good; cabin pressure is holding; suit pressure is Okay; 2 minutes and we got 4 g's; fuel is go; ah, feel the hand controller move just a hair there; cabin pressure is holding; 0₂is go; 25 amps." CapCom acknowledged, "Roger, we have GO here." Grissom then exclaimed, "And I see a star!"

The capsule separated from the booster and at 2 minutes and 33 seconds Grissom reported, "There went posigrades; capsule has separated. We are at zero g and turning around and the sun is really bright."

At 3 minutes 59 seconds, Grissom noted the effects of the absence of gravity, "Lots of stuff - there's lots of stuff floating around up here."

It was time for the retrorocket sequence. At 5 minutes and 5 seconds into the flight, CapCom called to Grissom, "Retros on my mark, 3, 2, 1, mark." Grissom reported, "Okay, there's 1 firing. There's 1 firing." CapCom acknowledged, "Roger, retro 1." Grissom continued, "There's two firing, nice little boost. There's three firing." CapCom radioed Grissom, "Roger, 3, all retros fired." Grissom responded, "Roger, roger. Okay, yeh, they fired out right there."

At 6 minutes and 8 seconds into the flight, Grissom reported, "Retro, I'm back on UHF and, ah, the jett - the retros have jettisoned. Now I can see the Cape and, oh boy, is that some sight."

At 7 minutes and 7 seconds CapCom asked Grissom about the view outside his capsule, "Roger, how does it look out your window now?" Grissom answered, "Ah, the sun is coming in and so all I can really see is just, ah, just darkness, the sky is very black."

Deceleration of the spacecraft in the atmosphere brought with it the onset of g forces. At 7 minutes and 54 seconds, Grissom reported, "I've got 0.05 g and roll rate has started." By 8 minutes and 11 seconds into the flight, the g forces had increased dramatically. Grissom reported, "Roger, g's are building, we're up to 6 [g]." Six seconds later, Grissom reported the g forces again, "There's 9 [g]." The g forces peaked and started tapering off. At 8 minutes and 19 seconds, Grissom reported, "There's about 10 [g]; the handle is out from under it; here I got a little pitch rate coming back through 7 [g].

At 8 minutes and 42 seconds Grissom reported, "Okay, I'm getting some contrails, evidently shock wave, 50,000 feet; I'm feeling good. I'm very good, everything is fine."

The time arrived for the parachute sequence to begin. At 9 minutes and 28 seconds, Grissom reported, "25,000 feet. Approaching drogue chute attitude. There's the drogue chute. The periscope has extended. This is ... we have a green drogue [light] here, 7 how do you read? Okay, we're coming down to 15,000 feet if anybody reads. We're on emergency flow rate; can see out of the periscope Okay. The drogue chute is good."

Soon it was time for the main parachute to deploy. At 10 minutes and 14 seconds, Grissom reported, "There goes the main chute; it's reefed; main chute is good; main chute is good; rate of descent is coming down, coming down to - there's 40 feet per second, 30 feet per, 32 feet per second on the main chute and the landing bag is out green."

The CapCom for recovery was called the Atlantic Ship CapCom (ATS) and he responded to Grissom, "Liberty Bell 7, Liberty Bell 7, this is the Atlantic Ship CapCom. Read you loud and clear. Our telemetry confirms your events. Over."

At 11 minutes and 42 seconds into the flight, Grissom reported, "Auto fuel and manual fuel has dumped." ATS CapCom responded, "Roger, roger."

Grissom continued, "And I'm in the process of putting the pins back in the door at this time. Okay, I'm passing down through 6000 feet, everything is good, ah, I'm going to open my faceplate. Hello, I can't get one; I can't get one door pin back in. I've tried and tried and I can't get it back in. And I'm coming, ATS, I'm passing through 5,000 feet and I don't think I have one of the door pins in." ATS CapCom responded, "Roger, Bell 7, roger."

At 13 minutes and 33 seconds into the flight, Grissom noticed a rip in his parachute. Grissom radioed, "Ah, roger, you might make a note that there is one small hole in my chute. It looks like it's about 6 inches by 6 inches - it's sort of a - actually it's a triangular rip I guess." ATS CapCom responded, "Roger, roger."

At 14 minutes and 54 seconds, Grissom reported his spacecraft status one more time before splashdown. Grissom radioed, "Okay. My max g was about 10.2; altimeter is 1000 [feet]; cabin pressure is coming toward 15 [psi]. Temperature is 90 [degrees F]." Grissom then continued with a report on his spacesuit parameters, "Coolant quantity is 30 [percent]; temperature is 68 [degrees F]; pressure is 14 [psi]; main O² is 60 [percent]; normal is - main is 60 [percent]; emergency is 100 [percent]; suit fan is normal; cabin fan is normal. We have 21 amps and I'm getting read for impact here."

Similar to Alan Shepard's flight, Grissom's lasted just over 15 minutes. The length of the flight was limited by the thrust and fuel constraints of the Redstone launch vehicle. At 15 minutes and 37 seconds into the flight, Liberty Bell 7 splashed down in the Atlantic Ocean.

After splashdown, Grissom was inside of his spacecraft bobbing in the Atlantic Ocean. Grissom radioed, "Okay, does anybody read Liberty Bell 7? Over." The call sign for the primary recovery helicopter was "Hunt Club 1." The recover helicopter responded, "Liberty Bell 7, Hunt Club 1 is now 2 miles southwest of you."

Grissom responded, "Roger, my condition is good; Okay, the capsule is floating, slowly coming vertical, have actuated the rescue aids. The reserve chute is jettisoned, in fact I can see it in the water and the whip antenna should be up."

After going through is post splashdown procedures, Grissom radioed, "Okay, Hunt Club, this is Liberty Bell 7. Are you ready for the pickup?" The helicopter crew responded, "This is Hunt Club 1; this is affirmative." Grissom continued, "Okay, latch on, then give me a call. I'll power down and blow the hatch, Okay?"

The helicopter crew acknowledged, "This is Hunt Club 1, roger, will give you a call when we're ready for you to blow." Grissom added, "Roger, I've unplugged my suit, so I'm kind of warm now so." The helicopter acknowledged, "1, roger."

Grissom radioed, "Now, if you tell me to, ah, your ready for me to blow, I'll have to take my helmet off, power down, and then blow the hatch." The helicopter crew confirmed, "1, roger, and when you blow the hatch, the collar will already be down there, waiting for you, and we're turning base at this time."

Unexpectedly, the escape hatch prematurely blew off of the side of the vehicle. Seawater from the ocean came pouring in through the open hatchway. At that point in the recovery process, a flotation collar had not yet been attached to the spacecraft.

If Liberty Bell 7 filled with water, it would sink to the bottom of the ocean. Grissom scrambled out of the hatch, trying to avoid the seafaring tradition of a captain going down with his ship. Grissom's problems did not end there. His space suit was not sealed and it too started to fill with seawater. Astronaut Grissom would drown if help did not arrive soon.

The recovery helicopter was attached to Liberty Bell 7 with a steel cable. The weight of the spacecraft became too much to bear as it filled with seawater. The straining helicopter developed engine trouble. Finally with no other alternative, the helicopter crew cut the cable holding Liberty Bell 7 and she was committed to the deep.

Before Grissom went under, the recovery crew rescued him. A concerned nation breathed a sigh of relief. After his recovery Grissom stated, "I was lying there, minding my own business, when I heard a dull thud."

The prime recovery ship for this mission was the USS Randolph.