What If: CH-47s available for D-Day

[wuzak]

This scenario is similar to that in The Final Countdown.

A storm passes over a US army base in Vietnam, and transports 200 CH-47s and their crews back to mid May 1944.

How would you use these for the D-Day invasion, a few weeks later?

Would you use them like C-47s and drop paratroopers from altitude?

Would you transport paratroopers, but land them on the ground?

Would you use them to transport equipment for use on D-Day?

C-47 top speed 224mph, service ceiling 26,400ft.
CH-47 top speed 195mph, service ceiling 20,000ft.

The CH-47's combat radius was much smaller than the C-47s, but at 230 miles that should be sufficient.

C-47 could take ~20 paratroopers.
CH-47 could take ~40, or up to 55 regular troops.

How would CH-47s fare with the German AAA defences? Would they be sitting ducks?

Would the CH-47s be held back until a few days after D-Day, after the beachhead has been established, and used for resupply?

 

[SaparotRob]

Before the grownups chime in, I'd have used them to land paratroopers instead of parachute or glider landings. The same LZs as had been trained for. It would keep the paratrooper groups together. A better chance to avoid floating down into flooded areas or smashing into trees, rocks or whatever with unpowered landings. There's gotta' a be a bit of WTF factor for the "thup thup thup".

 

[GrauGeist]

CH-47s were good for landing troops on point.
Moving material to the front in a situation like that would not have had much of an impact.

It would have been better to keep them operating within their original mission design: rapid deployment of troops.

 

[SaparotRob]

One thing occurred to me is maintenance. How many hours could the CH-47s operate before needing work?

 

[ThomasP]

Rhine crossing operations? 200x CH-47 with upto 40x troops each gives upto 8000x soldiers in a relatively precisely delivered manner. Plus the night operations capability.

 

[Frog]

This scenario is similar to that in The Final Countdown.

A storm passes over a US army base in Vietnam, and transports 200 CH-47s and their crews back to mid May 1944.

How would you use these for the D-Day invasion, a few weeks later?

Would you use them like C-47s and drop paratroopers from altitude?

Would you transport paratroopers, but land them on the ground?

Would you use them to transport equipment for use on D-Day?

C-47 top speed 224mph, service ceiling 26,400ft.
CH-47 top speed 195mph, service ceiling 20,000ft.

The CH-47's combat radius was much smaller than the C-47s, but at 230 miles that should be sufficient.

C-47 could take ~20 paratroopers.
CH-47 could take ~40, or up to 55 regular troops.

How would CH-47s fare with the German AAA defences? Would they be sitting ducks?

Would the CH-47s be held back until a few days after D-Day, after the beachhead has been established, and used for resupply?

A great part of the landing sites had been flooded by the Germans. The advantage of using these big choppers is that these flooding would have been quickly discovered, and the landing diverted to other sites, hence avoiding the many troops casualties and loss of materiel in the swamps.
Another advantage would have been a more accurate night assault.
For the flak it would have been the same thing as for the C-47.
Furthermore, the Chinook would have avoided the hazard of the gliders landings for the troops and matériel.

 

[muskeg13]

Hmmm? For (extra) special missions these CH-47s could carry M3 or modified M8 Scout Cars, jeep towed howitzers and antitank guns, and maybe even motorized heavy mortars or specially modified light tanks. A lot of firepower could be transported for "behind the lines" exploitation.

 

[wuzak]

One thing occurred to me is maintenance. How many hours could the CH-47s operate before needing work?

That's a very good question.

I would think that they should get a few weeks worth out of them, if they are doing the short trips.

 

[ARTESH]

What about Protection and Survivability?

 

[DerAdlerIstGelandet]

CH-47 Chinooks would not survive the D-Day beaches. Too much anti-aircraft fire. They would have to be limited to night time operations. And at night they would best be used for point to point troop movements and air assault.

 

[ThomasP]

Another thing to remember is that your grandfather's 1973 CH-47 was not as capable as today's CH-47. Not in terms of lifting power, protection/survivability, or maintainability/reliability/durability. Or in terms of add-ons (ie PAVE & navigation systems, or other electronics & hardware useful for missions, etc).

Without ready access to spares, repair and maintenance would be a problem. Wheels/tires could be replaced by similar wheel/tire items, or landing skids/pads could be fitted. But any serious repair/maintenance (ie engines, rotors, transmissions, fuel system, engine controls, flight controls, etc) would require cannibalization.

Fuel might be a problem in the immediate post-arrival period, but aviation kerosene (~US Jet A/UK Avtur) already existed and supply could be arranged if there was enough lead time before operations began.

 

[GrauGeist]

CH-47 Chinooks would not survive the D-Day beaches. Too much anti-aircraft fire. They would have to be limited to night time operations. And at night they would best be used for point to point troop movements and air assault.

Their ability to "get down in the weeds" would have provided better survivability than the gliders, which were committed to a glide path at a snail's pace, making them easy pickings for AA.

Same could be said for the paratroopers, where not only did they get picked off by AA, but small arms fire, too.

 

[DerAdlerIstGelandet]

Their ability to "get down in the weeds" would have provided better survivability than the gliders, which were committed to a glide path at a snail's pace, making them easy pickings for AA.

Same could be said for the paratroopers, where not only did they get picked off by AA, but small arms fire, too.

Agreed, but there is still a reason that the Chinooks in Iraq were restricted to night operations while the Black Hawks and Apaches conducted day and night ops.

 

[GTX]

On a tangent, I seem to recall CH-47s being introduced in something like this scenario in John Birmingham's Axis of Time series.

 

[wuzak]

CH-47 Chinooks would not survive the D-Day beaches. Too much anti-aircraft fire. They would have to be limited to night time operations. And at night they would best be used for point to point troop movements and air assault.

My original thought was that they would replace C-47s and Gliders in landing troops behind the landing beaches the night before the invasion.

I had thought to replace all C-47s/paratroopers with CH-47s, but there weren't enough CH-47s built to do that.

As to point to point air movements and assault, I would imagine that the CH-47 could place troops much closer to their objective - for example, unloading troops on a road a few miles from a bridge that needs securing.

 

[wuzak]

Agreed, but there is still a reason that the Chinooks in Iraq were restricted to night operations while the Black Hawks and Apaches conducted day and night ops.

Why could Black Hawks operate during the day, and Chinooks not?

Apaches have all their weapons to defend themselves.

 

[don4331]

My original thought was that they would replace C-47s and Gliders in landing troops behind the landing beaches the night before the invasion.

I had thought to replace all C-47s/paratroopers with CH-47s, but there weren't enough CH-47s built to do that.

As to point to point air movements and assault, I would imagine that the CH-47 could place troops much closer to their objective - for example, unloading troops on a road a few miles from a bridge that needs securing.

If you run a dozen CVE's into the Channel can't you make multiple flights during the night? Gliders were a one and done affair/C-47s have to go all the way back to an airstrip, but the WWII equivalent of an amphibious assault carrier a little ways off the coast would increase your lift substantially. Then convert the Skytrains into AC-47s - your Chinook crews should be aware of them.

And the CVE captain probably wouldn't be too upset by having all the avgas replaced by kerosene.

 

[GrauGeist]

Agreed, but there is still a reason that the Chinooks in Iraq were restricted to night operations while the Black Hawks and Apaches conducted day and night ops.

I would imagine that in the absence of high-tech AA during WWII, the Hook would have a better chance than it would have in modern times.

This is not to say that it would be invincible, but much more survivable.

Especially if it just thumped along over the treetops and the Germans seeing it for the first time, would have no idea WTF it was!

 

[Thumpalumpacus]

230 miles radius means the landing ops must be perfect, or the Allies know this time-storm will happen and have carriers stocked with jet fuel to get those heloes up and running again. Or simply do land-and-abandon.

Maybe we should add a wing of Buffs.

 

[DerAdlerIstGelandet]

I would imagine that in the absence of high-tech AA during WWII, the Hook would have a better chance than it would have in modern times.

This is not to say that it would be invincible, but much more survivable.

Especially if it just thumped along over the treetops and the Germans seeing it for the first time, would have no idea WTF it was!

I think it would be just as vulnerable to any kind of medium size AA or higher.