MacBook Air crashes, restarts and gives this error It keeps crashing and this is the newest one:

Anonymous UUID:       0BCEAA1D-32A3-1735-AF5F-607108F40027

Wed Jun 13 18:53:02 2018

*** Panic Report ***
panic(cpu 0 caller 0xffffff8016f154f0):  initproc exited -- exit reason namespace 2 subcode 0xa description: none

Thread 1 crashed

RAX: 0x0000000000000010, RBX: 0x00000001047f4f28, RCX: 0x00000001047a6a80, RDX: 0x00000001047f2000
RSP: 0x0000700003560250, RBP: 0x00007000035602f0, RSI: 0x000000000004b000, RDI: 0x00000001047f7410
R8:  0x0000000000000000, R9:  0x0000000000000e20, R10: 0x00000001047a6a10, R11: 0x0000000000000001
R12: 0x0000000000000001, R13: 0x0000000000001cf0, R14: 0x0000000000000001, R15: 0x0000000000000001
RFL: 0x0000000000010202, RIP: 0x00007fff6e9497c4, CS:  0x000000000000002b, SS:  0x0000000000000023

Thread 0: 0xffffff80258a8000
0x00007fff6ea9402a
0x00007fff6e915cc0
0x0000000000000000

Thread 1: 0xffffff802683f290
0x00007fff6e9497c4
0x00007fff6e94aa8d
0x00007fff6e94aca5
0x00007fff6e9521c4
0x00007fff6e9a45b1
0x00000001047c8c95
0x00000001047d89ea
0x00007fff6e909db8
0x00007fff6e91ce81
0x00007fff6e90c081
0x00007fff6e91e07a
0x00007fff6e911166
0x00007fff6e91ef0d
0x00007fff6e922d21
0x00007fff6ec5afd2
0x00007fff6ec5abe9
0x0000000000000000

Thread 2: 0xffffff8029432c70
0x00007fff6ea955b2
0x00007fff6e91ce81
0x00007fff6e90c081
0x00007fff6e91e07a
0x00007fff6e911166
0x00007fff6e91ef0d
0x00007fff6e922d21
0x00007fff6ec5afd2
0x00007fff6ec5abe9
0x0000000000000000

Thread 3: 0xffffff802c2c54f0
0x00007fff6ec5abdc

Thread 4: 0xffffff8027d56650
0x00007fff6ec5abdc


Mac OS version:
17F77

Kernel version:
Darwin Kernel Version 17.6.0: Tue May  8 15:22:16 PDT 2018; root:xnu-4570.61.1~1/RELEASE_X86_64
Kernel UUID: CC1699EE-71B5-3AF1-AAA3-6DBD16222B92
System model name: MacBookAir7,2 (Mac-937CB26E2E02BB01)
Root disk errors: "Could not recover SATA HDD after 5 attempts. Terminating."

EOF
Model: MacBookAir7,2, BootROM MBA71.0177.B00, 2 processors, Intel Core i5, 1.6 GHz, 4 GB, SMC 2.27f2
Graphics: Intel HD Graphics 6000, Intel HD Graphics 6000, Built-In
Memory Module: BANK 0/DIMM0, 2 GB, DDR3, 1600 MHz, 0x80AD, 0x483943434E4E4E384A544D4C41522D4E544D
Memory Module: BANK 1/DIMM0, 2 GB, DDR3, 1600 MHz, 0x80AD, 0x483943434E4E4E384A544D4C41522D4E544D
AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x117), Broadcom BCM43xx 1.0 (7.77.37.31.1a9)
Bluetooth: Version 6.0.6f2, 3 services, 27 devices, 1 incoming serial ports
Network Service: Wi-Fi, AirPort, en0
Serial ATA Device: APPLE SSD SM0256G, 251 GB
USB Device: USB 3.0 Bus
USB Device: BRCM20702 Hub
USB Device: Bluetooth USB Host Controller
Thunderbolt Bus: MacBook Air, Apple Inc., 27.2
Your drive is failing.
The key to this diagnosis is this error message in the panic report:
&gt; Root disk errors: &quot;Could not recover SATA HDD after 5 attempts.
&gt; Terminating.&quot;

To fully diagnose this, install macOS to an external drive.  If your MBA starts to function normally, you've narrowed it down to your drive.  (It can be a USB flash disk - it's only for testing purposes).
Luckily (as &quot;lucky&quot; as one can get in this scenario) the drive isn't soldered to the logic board so you do have the opportunity to replace it with another (128GB: PN# 656-0021A or 256GB PN# 661-02396).  It's not too difficult a fix, you just have to remove the back cover and disconnect the SSD.  ifixit.com has a good walk through.
Now, you DO have a backup, right?
If not, the good news is you can buy a sled or cable and attempt data transfer after you put a new drive in. Since reading data often works after writes to a failing drive are not happening. Sooner you power off and start data transfer the better.