SpaceX Interview Questions

About the Company: SpaceX

SpaceX is a private American company also known as Space Exploration Technologies Corp. It is headquartered in Hawthorne, California. It is founded in 2002 by Entrepreneur and CEO of the company, Elon Musk and currently has more than 6000 employees. SpaceX is famous for designing, manufacturing, and launching of advanced rockets and spacecraft. The main goal of the foundation of SpaceX was to reduce the cost of space transportation and enable people to live on other planets. SpaceX has successfully developed the Falcon launch family and dragon spacecraft family, and at present, both are working to deliver payloads into Earth Orbit.

Achievements of SpaceX

• SpaceX manufactured the first liquid-fueled rocket to reach orbit which was privately funded.
• SpaceX manufactured the first privately developed liquid-fueled rocket to put a commercial satellite in orbit.
• SpaceX is the first private company which has successfully launched orbit and also recovered a spacecraft.
• SpaceX is the first company, which has sent a spacecraft to the International Space station.
• SpaceX is the first company, which has sent a satellite into geosynchronous orbit.
• SpaceX was the first private company, which has successfully occurred the landing of an orbital rocket's first stage on land.
• SpaceX has launched world's most powerful operational rocket named as Falcon heavy in 2018.

Key people:

• Founder and CEO: Elon Musk
• President: Gwynne Shotwell
• CTO(Chief Technology Officer): Tom Mueller

Key Products:

• Falcon Launch Vehicles
• Dragon Capsules
• Merlin
• Raptor and Kestrel
• Rocket engines
• ASDS landing platform

Working Environment of the SpaceX:

SpaceX is one of the great company to work. It has a unique mission where people work to become part of the great history. SpaceX provides a smooth environment to their employees. If anyone joins the SpaceX, then he/she got an opportunity to work with the best engineers in the US. SpaceX provides great facilities for their employees. The communication hierarchy is very simple. Any employee can communicate with other employees as well as managers or CEO for a valid purpose.

How to apply and who can apply for SpaceX?

SpaceX provides two ways to work with their company, and there are several positions for which one can apply according to their skill-sets.

The two ways to get job in SpaceX:

• Full-time Job
• Internship

For both job types candidate can apply online through the link https://www.spacex.com/careers. By this link, one can check and apply for the current opening and opportunities in SpaceX. Once you apply for SpaceX and if your resume got selected, they will start your recruitment process.

Once you applied for SpaceX, you might have to wait for the long time of 2-5 months approx. Sometimes, you also get a chance after 2-3 weeks, but the candidate has to be patient.

SpaceX Recruitment Process

The recruitment process of SpaceX is very much different and it is one of the difficult recruitment processes. SpaceX has a very typical hiring strategy as they wanted one of the top talents across the world to work with them. The Whole process consists of several rounds and candidate has to give his best for every round. So, the candidate needs to prepare himself very well for the selection in SpaceX.

Following are the rounds which candidate need to go through for final selection.

1. First screening round starts where HR team select a much suitable resume out of the piles of applied resumes.
2. If Resume gets chosen, then applicants have to give second screening round which includes two to four telephonic interviews including with Coding MCQ.
3. If candidate clears the second screening round, then he got invited for the interview in SpaceX campus.
4. The Candidate now goes through the 7-8 face to face interview sessions.
5. After face-to-face interviews, there is one presentation round, in which candidate need to give a presentation on their projects.
6. After the presentation, there will be an engineering test, based on the fundamental questions.
7. In the whole process, if a single person has any doubt for selecting that candidate, then the process stops at that point and candidate sent back.

Sample C/C++ MCQ

1) Find the output for the following code:

#include<stdio.h>

int main()
{
       int x = 67,*m = &x;
       int *n=m;
       char *t=n;
       printf("%c %d",*t, *n);

}

1. C 67
2. Compile time error
3. C C
4. No output

2) Find the output for following code:

#include<stdio.h>
int main() {
int b=5;
b = printf("Quiz On");
printf(" ");
printf("%d", b);
return 0;
}

1. Compile time error
2. 5
3. Quiz On 5
4. Quiz On 7

3) Find the output for the following code:

#include <iostream>
using namespace std;
int main()
{
       char arr[11] = "Hello world";
       cout << arr;
       return 0;
}

1. Hello world
2. Hello worl
3. Compile time error
4. No output

4) Find the output for the following code:

#include <stdio.h>
void main()
{
       static int x;
       if (x++ < 2)
       {
            main();
            printf(" Hey ");
     }

}

1. Infinite times main call
2. Hey Hey Hey Hey
3. Compile time error
4. Hey Hey.

5) Find the output for the following code:

#include <stdio.h>
int main()
{
       int* p;
       *p = 20;
       printf("The value is = %d", *p);
     return 0;
}

1. Run time error
2. Compile time error
3. The value is 20
4. Garbage value

6) Find the output for the following code:

#include<stdio.h>
#include<stdlib.h>

  int main()
{
      int *ptr;
       ptr = (int *)malloc(sizeof(int)*5);
       if (ptr == NULL)
          printf("This is Null\n");
     else
   printf("This is Not Null");
 }

1. This is Null
2. This is not Null
3. Run time error
4. No output

7) Find the output for the following code:

void fun()

{
     static int i = 15;
     printf("%d ", ++i);

}
int main()
{
     fun();
     fun();
}

1. 15,16
2. 16,17
3. 17,18
4. 17,17

8) Find the output for the following code:

int main ()

{
   int x = 10;
 double y;
   printf ("%d", sizeof (++x + y--));
 printf (" %d ", x);
return 0;
}

1. 8 11
2. 10 10
3. 8 10
4. None of the above

9) Find the output for the following code:

#include<stdio.h>
int main()
{
int arr[] = {10, 20, 30, 40, 50, 60};
int *p= (int*)(&arr+1);
printf("%d ", *(p-1) );
return 0;
}

1. 10
2. 60
3. 20
4. Compile time error

10) Find the output for the following code:

#include <stdio.h>
int * arr[10];

int main()
{
if(*(arr+4) == *(arr+8))
{
printf("Pointer array are equal");
}
else
{
printf("Pointer array are Not Equal");
}
return 0;
}

1. Pointer array are equal
2. Pointer array are not equal
3. Compile time error
4. Run time error.

Technical Interview Questions

The technical questions of SpaceX are very tricky so, candidates must have a good knowledge of the position and related technologies, for which they have applied. As there are various face-to-face interview rounds so different interviewer can ask different types of questions. The types of questions can also vary as per different positions. SpaceX provides lots of career path for different roles.

A list of some interview questions with answers for the preparation of the interview.

1) Write a program to reverse the words using an array?

Output:

sihT si gnisrever eht sdrow

2) What do you understand by the Red black tree?

The Red-black tree is a type of self-balancing binary search tree with the extra attribute, which is the colour of the node. Colour of the node can be red or black that's why it is called as a Red-black tree. These colour attributes are used in the tree so that tree remains balanced (approx.) while insertion or deletion of a new node with time complexity of O(log n).

It requires the following rules:

• Each node will be of Red or Black colour
• The root node of the tree should be black.
• All leaf node should be of red colour.
• Child node and parent node cannot be of same colour.
• Every path from any given node to the NIL node will always have the same number of black nodes.

3) How will you reverse a linked list? Explain using a program?

Output:

Input linked list
85 69 60 35 18 15 
Reversed Linked list 
15 18 35 60 69 85 

4) What are the different sorting algorithms and their complexities?

The following is the list of sorting algorithm with their best and Worst case complexities:

5) Explain the pure virtual function?

A pure virtual function in C++ is a function which has declaration but does not have any implementation in the base class. It is declared with virtual keyword and assigned a value 0. The pure virtual function used in an abstract class. This is mainly a part of runtime polymorphism.

Syntax:

Example:

Output:

Area is %d 25

6) What is the use of register keyword in C?

In C language, we use storage class to define the scope and lifetime of the variable. The register is reserved keyword storage class. It gives hint to the compiler to store the variable in the register of memory. We can use register keyword for fast access of variable.

Syntax:

7) What are different types of typecasting in C++?

When we convert an expression from one data type to another data type, it is called as typecasting.

A list of different types of type casting in C++:

• Implicit conversion
• Explicit conversion
• dynamic-cast
• static_cast
• reinterpret_cast
• typeid
• const_cast

8) What is the functionality of "volatile" keyword?

The volatile keyword is a qualifier which is used with the variable at declaration, which tells the compiler that the value of the variable may be changed at any time, without taking any action.

Syntax:

9) Explain the differences between classes and objects in C++?

C++ is an object-oriented language and its object-oriented concept totally depends on its classes and objects. The class and objects both are the co-related with each other.

Some primary differences between classes and objects are:

10) Let's suppose, you're given two arrays of strings. How will you find whether all strings of first array are present in the second array, and return a Boolean value? Assume both arrays have millions of elements.

We can solve this problem using traversing and binary searching on the array. The first array should be traversed and then apply binary search on the second array.

11) What do you understand by "mutable" keyword?

• The mutable keyword is used as storage class specifier in C++.
• We can use the mutable keyword to modify one data member of a function without affecting other data members of that function.
• We can modify the data members of a constant object using the mutable keyword.
• We can use the mutable keyword only with non-static and non-const data members of a class.

Syntax:

12) Differentiate between a reference and a pointer?

Reference and pointers are the approximately same concept, with some differences. Both concepts are used to have one variable which can access another variable.

Following are the main differences between both the concepts.

• A pointer is used to store the address of other variables, whereas the reference is like a constant pointer, used to refer other value.
• A pointer can be re-assigned, whereas reference can only be assigned a value at time of initialization.
• We can perform pointer to pointer indirection, but we cannot perform reference to reference indirection.
• We can directly assign a NULL value for a pointer, whereas we cannot assign the NULL value directly to a reference.
• A pointer has its own memory area and address at the stack, whereas reference has same address as the main variable, but also have some memory space at the stack.

13) How can we get PID of the process in Ubuntu Linux?

PID is defined as a Process Identification Number. PID is a unique identification number which is automatically allocated to a process at the time of creation, in an operating system. To find the PID of the process in Ubuntu, Linux we can use the pidof command.

14) Differentiate between TCP and UDP?

TCP and UDP both are the transport layer protocols used for transmission of packets over the network. The primary difference between both the protocols are given below:

15) Write down the equation for lift?

To raise an aircraft into the air a force is required which is equal to or greater than the force of gravity, such type of force is called lift. Lift acts in an upward direction opposite to the gravity force. Lift equation can be written by using the Bernoulli equation which is:

P+1/2 ?V²= Constant and continuity equation

?*A*V= Constant, so lift equation will be:

Where Cl = coefficient

? = density

V= velocity

A = Wing area.

16) Explain the Null pointer?

A Null pointer has reserved value which shows that pointer is pointing to nothing or not a valid value. A Null pointer is mainly used to show the end of the list. A Null pointer can be useful for the following cases:

• A null pointer can be passed as a function argument, where we don't want to pass a valid memory address.
• A pointer is assigned as Null pointer variable when it is pointing to an invalid memory address.
• A null pointer can be used to perform error handling with pointers.

Syntax:

17) Tell me the size of an integer in 32-bit system?

The size of any data type in C depends upon compiler implementation so, the minimum size for an integer for the 32-bit system should be 2 bytes, and it may be 4 bytes or 8 bytes or more depending on the compiler.

18) Describe your Projects?

The answer to the above question will be different for each candidate. The interviewer wants a detailed explanation of the projects which have candidates have already performed. The Candidate needs to have a good knowledge for every project of the technology which he has used, a concept which he has used and even every small knowledge of the project is required.

19) How will you find a loop in a singly linked list?

Output:

10 8 12 5 4 
Cycle exist in list-->true

20) Is it possible to go to an infinite loop for the following program?

Ans: For the above program, it's not possible to go to an infinite loop. Even if we define arr_size to a negative value, still it will not go for infinite value.

21) According to you, which point of the cantilever is weakest?

The weakest point of cantilever depends on by which material the cantilever is constructed, and the weakest point is usually the free end.

22) Explain Reynold's number.

Reynold's number is a dimensionless quantity of fluid mechanics which is used to study the flow of a fluid. It determines the flow pattern of fluid in different fluid flow situations. It is useful in predicting the transition of flow pattern from laminar to turbulent flow. Reynold's number can be defined as the ratio of the inertia force to the viscous force within a liquid.

The Reynold's number can be given as:

Where,

?=density of fluid

u=velocity of fluid with respect to the object, ?= dynamic viscosity of the fluid

v=kinematics viscosity

Other questions which can be asked in SpaceX interview are following:

1. How will you control the temperature of something in Space? What will be your main limiting factor?
2. How will you apply and derive the stress equation?
3. What do you understand by composites?
4. Suppose you have a very large object which moving at very high speed, then how would you slow down it safely?
5. What will happen if you are running a high current (spot welding) through a nickel piece touching a copper piece?
6. How will you design fluid pipes on a crew model?
7. Write a function to parse a special formatted String to a tree structure?
8. Suppose there is a Red-black tree class written in C++, how to rebalance the tree?

HR Interview Questions

At SpaceX, there are various interview rounds, and many of those rounds contain technical and HR interview questions so, candidates need to be prepared in every round for technical questions as well as non-technical questions. The HR questions of SpaceX also very tricky, so candidates need to be very careful and prepare for these type of questions. There are some HR questions with best suitable answer, which can be asked in SpaceX interview.

1) How will you rate for your communication skill in between 1- 10? Explain with proper reason?

If the interviewer asks this question that means, he is expecting a candidate with excellent communication skill so, answer this question with confidence and in a positive way.

One can answer this question by using the following approach:

2) How will you manage your time, if you have plenty of work?

As SpaceX is well known for its long working hours so, it's very mandatory that candidate should have time management skills. It will be beneficial while doing work with SpaceX. So interviewer will ask this question so that they can judge whether you have that skill or not.

"Time management has always been an essential part of my life. For obtaining the time management, I create a list of work, then I prioritize the work according to the urgency. I also fix the deadlines to complete the assigned task. After completion of one task, I use to check the complete list that is there any task which have more priority and if a new task has been added to the list."

3) Why do you want to work at SpaceX? Explain?

For answering this question, you should be honest and tell what you think about SpaceX and what makes you excited to work at SpaceX.

See the following example:

"I want to work with SpaceX as I wanted to be a part of the company which makes history in the world so that I also can contribute a little bit of my knowledge towards the race to Mars, and SpaceX is one of those rare companies."

4) Are you also searching for Job in other companies?

When an interviewer asks this question, they want to check how much serious you are for your career. So for answering this question, you should be very careful and try not to take the other companies name for which you have applied. Following is the example for this question.

"I have recently started searching for the job and also got the offer from some of the companies, but for this position in SpaceX, I was very much excited for a long time."

5) What do you like to do apart from work?

"When I get free from my work, I play badminton, and I also love to listen to music and reading novels."

6) What is success according to you?

"According to me success is feeling of maximum satisfaction and happiness, which you get from yourself after accomplishing a goal and if someone is completing his goals, that means he is getting success in his life."

7) *Why should we hire you at SpaceX?

SpaceX hires the best talent among lots of candidates, and if any of the interviewers will not satisfy with your answer, then the process stops immediately, so candidate should be cautious while answering this question. The interviewer wants to know that how much you think that you are suitable for that particular role. Candidate should respond by telling what different skill set or prior experience he has, which will be suitable for that role. One of the possible way to answers this question is:

"I have prior experience in aerospace technology, and also I have good theoretical and practical knowledge in space technology, with good communication skills and confidence which makes me most suitable for this role."

8) Do you think, that it is possible to be a good team member, but you do not agree with your team leader?

By this interviewer wants to check that how will you deal if you are a good team member but not agree with the leader, he wants to check whether you will handle it positively or negatively, so try to answer confidently and little bit diplomatically.

"Yes I believe, it might be a situation where my team leader and I do not have same thoughts, but still I will always put my thought with complete respect showing towards him as he is our leader and try to come at a point to apply that decision which is beneficial for everyone."

9) As I can see in your resume you have multiple gaps between employments, what was the reason for these gaps?

If you have various gaps during the employments, then it may be a tough question for you. But while answering this, you must be honest as if you will lie you can be caught, so whatever was the reason, clearly specify that reason.

"The main reason for these gaps was to get hired in the best company. Although I got various offers during the job search, still I wanted to join the best among those so that I can work for them for a long time".

10) Who is your inspiration for life?

This is the favourite question for most of the interviews and same for SpaceX. This is the most asked question because by this question, interviewer checks what your mindset is and what things motivate you in your life. As everyone has someone who motivates and inspire him so this is an easy question, and you can answer impressively. There is an example for this question:

"My inspiration of the life is Mr. APJ Abdul Kalam. From my childhood, my father used to tell me about him, since that time I was very inspired by him. I got inspired not only by his skills and knowledge but also by his personality and his noble thoughts. He was one of the great Indian scientists with an extraordinary character. He has faced lots of challenges in his life but never left moving, which really motivates me never to give up. Whenever I think that I can't do anything I just read some great thoughts written by him and again get a power to do things in a new way and with new energy."

11) If you face a heavy workload at SpaceX, then how will you make a balance between your life and work?

As we know that SpaceX is well known for its long working hours so, before hiring any candidate, HR manager will ensure that whether a candidate is suitable for the environment or not. So before going for SpaceX one should be mentally and physically prepare for working for long hours.

"As I have great time management skills, which will help me to keep a balance between my life and work. I always try to do work as per their priority. And if you love your work, then time duration will not produce any restriction."

12) Which is your proudest achievement till date?

The interviewer would like to know your goal setting and reaching criteria. Every hiring manager wants to hire a candidate with a vision. So by telling achievement, candidate can tell them what their goal achieving capability is.

"I have won the award for the innovative employee of the month in my last company. We have given a project, which was needed great innovation for the accomplishment of that project, and I decided to be the leader for that, and I with my team have successfully completed that project, and also that was one the of the best project of the company."

13) How would you inspire and encourage ideas in others?

The interviewer wants to check your leadership qualities and thinking capability by this question. This is the quality which makes you different from others and also opens a door for some new opportunity in the future. This should be answered in a very innovative way. One of the possible answers to this question is following.

"If I get a chance to inspire or encourage ideas in others, then I will encourage other people to be creative for their work and will make a platform on which they can present their ideas, and I will also praise for their efforts publicly, which will motivate them and inspire others."

14) At SpaceX, confidentially is most significant for us. If you get hired would you sign a confidential agreement with us?

Confidentiality is very important rule for SpaceX, so interviewer will ensure whether you are ready to follow such type of rules or not. So before answering this question, candidate should ensure themselves to follow these rules. Candidate can answer this question in following way:

"As I am very loyal for my work so, I will also be loyal for my employer, and if I get hired, I will surely sign a confidential agreement with SpaceX without any trouble."

15) Do you think that you have progressed in your career according to your expectations?

This is the little tricky question as by this interviewer will check your career goals and how long you want to go in your career. This question can be answered by telling about your achievements and further goals.

16) In your opinion, what makes us more powerful than others?

Before applying for any company, you must have a deep search for the company only then you can answer this, by this question interviewer want to know that how much you know about the company, what are their specialities which makes them different and more powerful than others.

"As SpaceX has a very different vision of creating the spacecraft more efficient with less cost, and SpaceX is preparing a tour for people to the Mars, and the SpaceX has the world['s best talent which is like armed force which is prepared to do their best. All these things makes SpaceX more powerful than others."

17) How you get interested to work with SpaceX?

When we started to apply for such a big company, we must have a vision and also something which generates enthusiasm and motivation to work with such companies. Everyone has some vision which generates interest to work with the SpaceX. This can be answered by following way:

"When I was a kid, I always being very excited when I heard about galaxies, planets, and astronauts. This excitement got increased day by day, and I started to search about those things on internet. After my Intermediate I did engineering with astronomy, and then I heard about SpaceX, at that time only I decided to work with SpaceX, and now I am here to live my dream."

18) What is your unique work style/ what would be your strategy for a task?

By above question, interviewer wants to know how efficiently you can perform a given task and what your approach for doing a task is. By answering this question in unique way candidate can impact a good impression.

"My work Strategy for doing any task is little bit different, I prefer to do work by enjoying it, which increases my efficiency. Firstly, I prioritize the tasks and start doing task with one by one, if I face any issue in some task even after I tried my best for that then I take some rest and think about what is exactly the issue after finding the solution, I restart my work and do it in more efficient way. I set a goal for every task with time duration and always try to achieve that goal before the completion of time."

19) If you have a choice, then which type of task would you select to do at last?

"If I would have a choice I would select a task for last, which will require more time but not require much energy and knowledge."

20) We have a policy of background verification for employees, which includes criminal background verification, educational verification, and prior experience verification, are you willing to comply with us?

Nowadays, every company has such policy of background verification, to ensure that there should not be any criminal background and all the required documents are correct or not. And to comply with this is not an issue.

"Sure, I will comply for background verification, and I think this is also required for every company to know about their employees, to who they hire, and I don't have any issue with this."

Some other questions generally asked in SpaceX interview:

1. We have strong competitors in this industry so, according to you in which part we should improve ourselves to be a top rated company?
2. How much innovative you are and how it can be helpful for your work to improve your performance?
3. There are lots of skills which are required for this role and I have just checked your resume but you don't have those skills. How will you learn those skills?
4. There are various career paths available in SpaceX. For which career path you are most interested?
5. Have you ever shown your leadership ability, when you were not a leader?
6. How do you want to be recognized for your accomplishment in SpaceX?
7. How do you think that your prior experience will help you in this position?
8. We only hire a candidate with experience in aerospace engineering at SpaceX. In which industry you are more experienced, public or private?
9. Are you able to work for 60 hours in a Week?
10. If you will be hired, can you work overtime?