20230401_ROKAF_Academy_Command

 1. Black Eagles

 As always, Black Eagles demonstrate their best show in this event.  

 2. Weaponary

 Some static display items, 20mm gun from F-5, unguided rockets, SDB, and 2000lb GBU. 

 3. Others

 APC, SAMs, and other old aircraft. 

Missile-SIM : Performance Evaluation for Impact of Missile-Size

Previous Work Status

Initial Version of Missile-SIM for Performance evaluation
Aerodynamic Validation of Missile-SIM for Trajectory 
AIM-120C Study using Missile-SIM : Part 1 - Sensitivity
AIM-120C Study using Missile-SIM : Part 2 - Launch Condition
AIM-120C Study using Missile-SIM : Part 2 - Launch Condition - revision
Patch note of Missile-SIM : Guidance Algorithm is added w/ Real-Time plot
W.I.P status of Missile-SIM : Addition of Air-propulsion part 1
W.I.P status of Missile-SIM : Addition of Air-propulsion part 2
AIM-120C Study using Missile-SIM : Part 3 - CUDA / LREW / METEOR types. 1 : Baseline Comparison
AIM-120C Study using Missile-SIM : Part 3 - CUDA / LREW / METEOR types. 2 : Sensitivity Analysis
AIM-120C Study using Missile-SIM : Part 3 - CUDA / LREW / METEOR types. 3 : Few mentions
W.I.P status of Missile-SIM : Addition of 3D Coordinate
W.I.P status of Missile-SIM : Development of Few generic bodies for Further Missile-SIM
Missile-SIM : Performance Evaluation for ATACMS class missile
Missile-SIM : Performance Evaluation for KM-SAM class missile
Missile-SIM : Effectiveness of Rocket motor for free-fall bomb
Missile-SIM : Performance Evaluation for Iskander / Kh-47M2 Kinzhal & ATACMS+Booster

 1. Modeling of Candidates for SIZE-EFFECT

 While I was coding Flight-SIM, I had curiosity about impact of the size of the missile. It is generally known that larger missile can preserve its kinematic energy and has advantage for longer range. 

 However, how much advantage the larger-missile have ?

 As the size of the missile grows, slender ratio (l/d), propellant/weight ratio, and aerodynamic configuration (fin size and shape) are changed. So, it is hard to evaluate the pure impact of the size. 

 At this time, I could simulate the different size of the missile with same aerodynamic-coefficient, propellant/weight ratio. It is unrealistic, because smaller air-to-air missile generally has slender profile, smaller propellant/weight ratio. Purpose of this study is only for sensitivity study for missile-size.  

 2. Missile-SIM Result


 Simulation has been conducted for Sea-level, 15kft, 30kft for M0.5 launch conditions. Size of the missile has been varied from AIM-9's to Massive S300 SAM class. The result shows that the larger missile has slightly higher speed however difference is small compared to its size difference. 

 As we expected, real-difference between small and big missiles can be shown in after-burn-out phase of the missile. Because relation between weight, proportional to the dimension^3, and drag, to the dimension^2, made larger missile could glide longer range with maintained speed. 

 In Sea-level, AIM-9 one almost loses its energy symmetry to its burn-phase while AIM-120 class reaches twice of that, AIM-54 class three-times, and S-300 class four-times. 

 Due to this result, it is natural that Point-Defense Anti-Air warfare(<30km) has missile smaller than AIM-120 class, like MICA-VL, ASTOR15, Sea-Sparrow, Sea-RAM, Crotale, and ESSM. Larger than AIM-120 class is excessive and in-practical. 


 At the higher altitude, difference become larger. Although smaller missile could achieve longer range, AIM-54 and S-300 sized missile goes longer than 100km, without following trajectory course. 


 From this result, we could understand why each nation develop own missile for different size. US, usually operating offensive counter air, will develop smaller missile to carry more missiles in limited payload for longer mission. (And offensive mission should encounter shorter range of engagement). Eastern side should develop larger missile to perform aerial-denial for high-value asset of western side. 

<Sea Level>

<15kft>

<30kft>

Missile-SIM : Performance Evaluation for Iskander / Kh-47M2 Kinzhal & ATACMS+Booster

Previous Work Status

Initial Version of Missile-SIM for Performance evaluation
Aerodynamic Validation of Missile-SIM for Trajectory 
AIM-120C Study using Missile-SIM : Part 1 - Sensitivity
AIM-120C Study using Missile-SIM : Part 2 - Launch Condition
AIM-120C Study using Missile-SIM : Part 2 - Launch Condition - revision
Patch note of Missile-SIM : Guidance Algorithm is added w/ Real-Time plot
W.I.P status of Missile-SIM : Addition of Air-propulsion part 1
W.I.P status of Missile-SIM : Addition of Air-propulsion part 2
AIM-120C Study using Missile-SIM : Part 3 - CUDA / LREW / METEOR types. 1 : Baseline Comparison
AIM-120C Study using Missile-SIM : Part 3 - CUDA / LREW / METEOR types. 2 : Sensitivity Analysis
AIM-120C Study using Missile-SIM : Part 3 - CUDA / LREW / METEOR types. 3 : Few mentions
W.I.P status of Missile-SIM : Addition of 3D Coordinate
W.I.P status of Missile-SIM : Development of Few generic bodies for Further Missile-SIM
Missile-SIM : Performance Evaluation for ATACMS class missile
Missile-SIM : Performance Evaluation for KM-SAM class missile
Missile-SIM : Effectiveness of Rocket motor for free-fall bomb

 1. Modeling of Iskander / Kh-47M2 & ATACMS + Booster - OUTDATED

 Geometry related to aerodynamics Iskander and its modeling is shown below.

- This article is outdated; New Ballistics Analysis based on this CFD result is here

https://jaesan-aero.blogspot.com/2022/03/few-ballistic-missile-analysis-w_19.html

 Except booster part, ATACMS part is same as the previous model
(Missile-SIM : Performance Evaluation for ATACMS class missile)


  2. Trajectory Simulation of the Iskander / Kinzhal and ATACMS w/ Booster

 Based on the modeled missile, I simulated a few trajectory options using Missile-SIM. 


1) Normal version of Iskander (~170km)

It has normal short range ballistic missile characteristics; peak altitude is about 40km w/ <M5 burn out velocity. 

2) Iskander-M (~250km)

Bigger ISP, slightly larger amount of propellant and better trajectory gives significantly better range than the normal version. 

3) Iskander-M (~350km)

The projectile after burning whole fuel has less drag at the high altitude. Indeed if the missile glide less deeper angle, range could be extended.

4) Iskander-M (~500km)

Its maximum range is about 500km. Iskander-M missile could cover the entire Korean peninsula.

5) Iskander-M as Kinzhal = Air-launched Iskander from MiG-31 (~170km)

If the Iskander-M were launched at 40,000ft w/ M1.3, range is increased about 1,000km class. Because missile enter the 'almost-no-drag' altitude, missile has much higher burn-out velocity and longer range. 

6) ATACMS+Booster (~500km)

If we given the ATACMS booster, range become similar to that of Iskander-M. (However, ATACMS has smaller warhead weight than that of Iskander-M)

7) Air-Launched ATACMS+Booster

JTACMS in the previous article (Missile-SIM : Performance Evaluation for ATACMS class missile) shows about 250km class range. 

 If we attached booster for JTACMS, what happens? 

 Similar to Iskander-M, it could extend its range for more than 1,000km. 

3. Conclusion

 Boosted ATACMS and Iskander-M model are compared for ground and air-launched version. Both missiles having several hundred kilometer range could have extended range using air-launched method. 

I also tested hypersonic glider or three-stage rocket however, these have almost infinite range as intercontinental weapon. Indeed, I decided not to study seriously about them (as shown below)

From now on, I will focus on the upgrade of Missile-SIM as Flight-SIM for more advanced vehicle
(Supersonic Civil Aviation Area)



Appendix : Hypersonic Glider case (Almost act like a LEO projectile)