ED Forums - View Single Post - Next F-14 video by MagzTV
View Single Post
Old 01-06-2019, 03:25 PM   #15
BlackLion213
Senior Member
 
BlackLion213's Avatar
 
Join Date: Mar 2015
Location: San Fransciso Bay Area
Posts: 1,479
Default

Quote:
Originally Posted by Gunslinger22 View Post
Man I just love watching anything F-14 related at the moment! This was actually a very good video, though I found his comments about the FM very contradictory to everything I’ve read and seen so far. He mentions that the Tomcat is nearly idiot proof and that it feels much like a FBW airframe. Though from what Jabbers and Ralfie have said, it’s apparently very hands on and will punish any inputs that aren’t correct to the situation. He even mentions that it’s very hard to stall and that you have to nearly enduce a flat spin providing thrust isn’t asymmetrical. Just found that strange that his views could be so different. Either way I’m happy!
The different videos are approaching handling in different ways. Ralfi and Jabbers are comparing more directly to other modern DCS offerings and were rather surprised that their standard techniques for ACM were not working well in the F-14. The onset of roll reversal requires the virtual pilot to stop using lateral stick for roll, but the pilot also has to monitor where they are in the AOA range to know when to make this transition along with managing overall performance.

Magz was approaching handling from a more general perspective and much of what he was comparing to are WWII warbirds in terms of stability. Compared to a platform like that, the F-14 is very stable and will not drop a wing or develop any sudden uncommanded movements as you push to very high AOA. Once AOA goes above 20 or so, any sideslip may result in wing rock (not easy to track a target with wing rock), but the aircraft won't slice or roll off in this regimen. As AOA increases above 25-30 units, there is a tendency to roll off that may need rudder inputs for correction (not lateral stick!), but you can push the F-14 to very high AOA despite no FBW with excellent controllability.

This was one of the major breakthroughs for the F-14 versus older platforms when it first arrived, it allowed pilots to really push AOA to very high levels while still maintaining controllability and not departing. Part of this was related to the wing rock - the wing rock stabilizes the aircraft as it moves into negative yaw stability at high AOA due to adverse yaw with roll. As sideslip develops dihedral effect of the airframe induces roll, but because that initial roll causes the nose to yaw away from the direction of roll it pushes the nose back to center.

Where the F-14 starts to develop wing rock, the Phantom was prone to departure (roll off for the slatted F-4s and yaw off for the unslatted). So with pure pitch inputs, its hard to get into trouble with the F-14 (like nearly all the jets in DCS). However, you can get into trouble with poorly chosen inputs (like Ralfi and Jabbers described/demonstrated).

So if you give lateral stick above 20 units, you get roll opposite stick along with sideslip and the potential to develop yaw rate. If you hold that lateral stick past about 90-120 degrees of roll the yaw rate becomes pretty visible and could lead to a real departure. Similarly, you use rudder for rolling at ~17+ units AOA, but the roll SAS will cross-control your rudder inputs since it only monitors stick inputs for whether roll is "commanded". If you rudder roll with roll SAS on, most the time it is fine, but every so often it will cross control and create a significant yaw moment.

And at high AOA, you do did not monitor for excessive yaw rates in general, but things tend not to come out of no where.

So the F-14 is very hands on imho, but most of the dangerous things are due to bad pilot inputs not the aircraft deciding to take a swing at you.

-Nick
BlackLion213 is offline   Reply With Quote