Moderators: richierich, ua900, PanAm_DC10, hOMSaR

 
User avatar
Channex757
Topic Author
Posts: 2394
Joined: Sat Jun 18, 2016 7:07 am

C-5 reverse thrust question

Fri Feb 03, 2017 4:54 pm

Quick question for any former C-5 drivers or anyone with knowledge of their systems.

One thing I've noticed is on touchdown, the C-5 seems to take longer between wheels hitting the deck and reverse thrust engagement. Is this a training or a systems issue?

Certainly a lot longer than a comparable civilian widebody would take. Anyone able to shed light on this or am I imagining things...?
 
JohnM
Posts: 395
Joined: Sat Feb 24, 2001 12:35 pm

Re: C-5 reverse thrust question

Mon Feb 06, 2017 7:51 pm

I'm not in the loop as far a some checklist procedures go. However I did maintain that system on the A &B models. Engines 1 & 4 are locked out from reverse thrust, and engines 2 & 3 are limited to idle reverse thrust in flight due to the touchdown system. It is an electrical linear actuator that does this in the throttle quadrant. Upon landing 3 things will allow the throttles to be pulled back to reverse thrust. 1) touchdown signal from both forward main landing gears, 2) touchdown signal from the both aft MLGs, or 3) MLG wheel spin up signal which takes 1 anti skid signal from each MLG. The wheel spin up system is there to allow the airplane to "know" it has decent ground contact and allow faster T/R deployment, and works before touchdown normally, especially if the jet is floating without hard contact.

The C-5 "legacy" (A and B) model T/Rs are fairly complex. The delay you see might be the yoke actuators (pilots) making sure all T/Rs are actually deployed before pulling further aft on the throttles. They can check for deployment, if good, further aft throttle movement will spool the engines up. That part is purely my guess. The M uses solenoids to do what the linear actuator used to do. The M uses bleed air actuated T/Rs being a CF-6, while the old TF-39s were hydraulic actuation. I think deployment speed is similar however.

Who is online

Users browsing this forum: No registered users and 22 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos