Concerns about mass distribution on the stack Orion-National Team Lander

[Star-Ram]

I've seen some animations, specifically from Scott Manley, and he places the docking port for National Team lander, just on one side of the "first story" of the lander. I am not sure if it will be so, but I immediately remembered the movie "Apollo 13" when Commander Jim Lovell was self-training to handle the new stack of LM-CSM ftom LM's cockpit, after their accident. "It is like trying to go on bicycle with an elephant piggyback", he said or something like that, and I figured out a similar case on the stack formed by Orion and this brand new lander... if what the animation shows is true, Jumbo wouldn't go piggyback, but hanging on a "side car"... I'm concerned with the docking port on one side: Apollo 13  tought us how much important is that the engine thrust vector ran through the gravity axis of the stack. to avoid a force's moment of rotation. If the National Team lander had to work as a lifeboat, in case of Orion's main engines incapacitation, they'd be forced to carry Orion at least back for being the only one that has heat shield available... so, Orion would be a real dead weight hanging on one side in case that Lander engines were to save the day. At least, I'd add a capture point (not necessarily with an acces on it) for Orion down in the center and outside the lander cockpit's floor, so, I'd be sure to have all the stack's mass aligned in the same Thrust vector in case it would become necessary.

[mkent]

Orion doesn’t dock directly to Blue Moon.  They each dock to Gateway.

[arthuroMo]

Orion doesn’t dock directly to Blue Moon.  They each dock to Gateway.

I think there's a requirement to do so, but only is rescue situation.

[Jim]

I've seen some animations, specifically from Scott Manley, and he places the docking port for National Team lander, just on one side of the "first story" of the lander. I am not sure if it will be so, but I immediately remembered the movie "Apollo 13" when Commander Jim Lovell was self-training to handle the new stack of LM-CSM ftom LM's cockpit, after their accident. "It is like trying to go on bicycle with an elephant piggyback", he said or something like that, and I figured out a similar case on the stack formed by Orion and this brand new lander... if what the animation shows is true, Jumbo wouldn't go piggyback, but hanging on a "side car"... I'm concerned with the docking port on one side: Apollo 13  tought us how much important is that the engine thrust vector ran through the gravity axis of the stack. to avoid a force's moment of rotation. If the National Team lander had to work as a lifeboat, in case of Orion's main engines incapacitation, they'd be forced to carry Orion at least back for being the only one that has heat shield available... so, Orion would be a real dead weight hanging on one side in case that Lander engines were to save the day. At least, I'd add a capture point (not necessarily with an acces on it) for Orion down in the center and outside the lander cockpit's floor, so, I'd be sure to have all the stack's mass aligned in the same Thrust vector in case it would become necessary.

doesn't matter now days with fly by wire.

[Jim]

If the National Team lander had to work as a lifeboat, in case of Orion's main engines incapacitation, they'd be forced to carry Orion at least back for being the only one that has heat shield available...

Not going to happen. 
A.  Gateway is the lifeboat.
b.  Lander is not going to get them back to earth, it will have been expended.
Lander stages at Gateway, Orion goes to Gateway.  Lander goes to the moon and returns to Gateway.  Then this is the only time the crew would discover Orion engines not viable.

Apollo does not map to Artemis one to one. Not all Apollo procedures, processes or lessons learned are applicable to Artemis.

[TrevorMonty]

If the National Team lander had to work as a lifeboat, in case of Orion's main engines incapacitation, they'd be forced to carry Orion at least back for being the only one that has heat shield available...

Not going to happen. 
A.  Gateway is the lifeboat.
b.  Lander is not going to get them back to earth, it will have been expended.
Lander stages at Gateway, Orion goes to Gateway.  Lander goes to the moon and returns to Gateway.  Then this is the only time the crew would discover Orion engines not viable.

Apollo does not map to Artemis one to one. Not all Apollo procedures, processes or lessons learned are applicable to Artemis.

If the lander was refuelled would enough DV to take crew to LEO.

[Eric Hedman]

I've seen some animations, specifically from Scott Manley, and he places the docking port for National Team lander, just on one side of the "first story" of the lander. I am not sure if it will be so, but I immediately remembered the movie "Apollo 13" when Commander Jim Lovell was self-training to handle the new stack of LM-CSM ftom LM's cockpit, after their accident. "It is like trying to go on bicycle with an elephant piggyback", he said

I went to a presentation on Apollo 13 in Oshkosh by Jim Lovell and Fred Haise.  They said the scene where Jim Lovell is flying the stack for the final course correction was a massive exaggeration by Ron Howard the Director of the movie.  It was not flying wildly in all directions in real life as shown in the movie.  Lovell said the telemetry showed that the worst deviation from the direction they should be pointing during the course correction burn was less than half a degree.  The wild gyrations in the movie was a Hollywood decision to add drama.  There were other dramatic modifications to reality in the movie.

[DigitalMan]

I don't have anything to do with https://apolloinrealtime.org/, nor do I even know the folks who created it, but it's a great place to replay the Apollo 13 mission.

[ccdengr]

doesn't matter now days with fly by wire.

Apollo was fly by wire too, and LM attitude control of the stack was always a planned backup mode.  As noted, whatever the movie showed was exaggerated for dramatic purposes.

See section V-E of https://ntrs.nasa.gov/api/citations/20090026451/downloads/20090026451.pdf for details.

DPS-1 was performed with the LM DPS and the LM PGNS. A DPS firing with the LM docked to the CSM was
first performed in low Earth orbit during the Apollo 9 mission (March 1969) to test the DPS backup capability for
the SPS.  For the maneuver to burn attitude the crew used Flight Director Attitude Indicator (FDAI) error needles
driven by the AGS as cues. The Thrust/Translation Controller Assembly (TTCA) was used for
roll and pitch control, and the Attitude Controller Assembly (ACA) for yaw. The ACA was normally
used for manual attitude control during LM only flight. However, use of the TTCA for pitch and roll control was
required since it provided more pitch and roll control authority than the ACA when the LM RCS was used to control
the docked CSM/LM spacecraft with a fully loaded SM.

[Paul451]

I've seen some animations, specifically from Scott Manley, and he places the docking port for National Team lander, just on one side of the "first story" of the lander. I am not sure if it will be so, but I immediately remembered the movie "Apollo 13" when Commander Jim Lovell was self-training to handle the new stack of LM-CSM ftom LM's cockpit, after their accident. "It is like trying to go on bicycle with an elephant piggyback", he said or something like that, and I figured out a similar case on the stack formed by Orion and this brand new lander... if what the animation shows is true, Jumbo wouldn't go piggyback, but hanging on a "side car"... I'm concerned with the docking port on one side: Apollo 13  tought us how much important is that the engine thrust vector ran through the gravity axis of the stack. to avoid a force's moment of rotation. If the National Team lander had to work as a lifeboat, in case of Orion's main engines incapacitation, they'd be forced to carry Orion at least back for being the only one that has heat shield available... so, Orion would be a real dead weight hanging on one side in case that Lander engines were to save the day. At least, I'd add a capture point (not necessarily with an acces on it) for Orion down in the center and outside the lander cockpit's floor, so, I'd be sure to have all the stack's mass aligned in the same Thrust vector in case it would become necessary.

Put simply, the image is wrong. The lander won't manoeuvre while Orion is attached.

Apollo CM+SM docked with the LM in Earth orbit and pushed it to lunar orbit, travelling the entire journey together. During A13, the LM was used as a lifeboat for the return trajectory as well, hence the need for manoeuvres during key points in the flight.

By contrast, the NT lander and Orion will each travel to the moon by their own means. (With the lander arriving in lunar orbit well before its crew launches from Earth.) Orion will only dock with the lander (either directly, or via Gateway) in lunar orbit to transfer the crew.

Hence, an Apollo-13 scenario won't happen, since Orion would be dead before reaching lunar orbit. LoM/LoC.